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40+ Easy Science Experiments For Students: Lots Of Great Ideas

Categories Activities & Ideas

Science is one of the most intriguing subjects to learn in school. It’s so varied and it can be a lot of fun for kids – especially when it comes to conducting science experiments. However, science experiments do not always have to be about beakers and bunsen burners. There are several ways that students can conduct easy science experiments, and it does not require a lot of resources or money to do so.

But what exactly are the options?

Well, if you are a teacher or a parent looking for easy science experiments for students, then we’ve got you covered. Our comprehensive list below shows you plenty of options that they can take part in.

So, if you’re ready to find out a lot more – then read on for lots of ideas!

Easy Science Experiments For Students! 

Without any further delays, let’s dive right into this list of some easy science experiments for students. We’re sure that your young minds will love some of these!

1. Dancing Pepper

Perhaps one of the most intriguing and fun experiments is the dancing pepper experiment. It shows kids how substances behave differently when placed on water in an effort to show how molecular behavior can differ with surface tension.

This can result in some things appearing to dance, so it’s a pretty fun experiment to observe! 

2. Colored Celery 

This is a pretty basic experiment but it can help to show kids how plants absorb water. You just need either celery or a white flower and some colored water. Once the celery is placed in the colored water, it can help kids to visualize how plants sustain themselves.

3. Dissolve Or Not?

This experiment can help teach kids about different solutions, but it’s more about showing kids the way to create their own hypotheses. For example, having six different substances and six different solutions, questioning whether it will dissolve and why they think so. 

4. Volcano (Baking Soda)

Every kid will have fond memories of this experiment. It’s a super fun and easy science experiment that shows how bases and acids react when they are in contact with one another, and it results in a miniature volcano! 

5. The Skittles Experiment 

This is a cool way to learn about diffusion. You simply need a packet of Skittles and observe what happens when each different color coating is exposed to shallow, cold or hot water. 

6. Burn The Bill 

Don’t panic, you won’t be burning any money with this experiment . It’s an easy way to teach kids about combustion, so you can use any paper item. 

7. Dr. Seuss’ Butter Experiment

Any fans of Dr. Seuss may recognize this experiment. You simply need to put heavy whipping cream into a tight jar and observe how the fat molecules clump together and form a butter product!

8. Liquids And Layers 

Using items that you can find in your pantry, this experiment can help to show kids how liquids have different densities and how they might operate.

9. Egg Crystal Geode 

Merging Springtime and Geology together, this is a fun experiment whereby kids can make their own geodes and learn about super-saturated solutions.

10. Make Rain In A Jar 

This quick and simple experiment can help to show students how rain occurs. As we know, rain is the result of warm, humid air converging with cold air in the upper atmosphere. 

So, using a jar and a plate, you can place ice and water into a jar and show kids how rain works by making your own in a jar! 

11. The Unpoppable Balloon 

Students will be intrigued by how you can put a sharp stick through a balloon and it won’t pop! It’s a quick and simple experiment that demonstrates polymers.

12. Float Or Sink?

This experiment is pretty basic but it’s quite important to learn. It can be conducted anywhere too, but it’s best during hot weather using a lake or river. 

Create a hypothesis with multiple items and question whether or not you believe certain items will sink or float. 

13. Make Your Own Sand 

Any kid will get a kick out of making their own sand ! The experiment doesn’t need too many resources or items, but it’s something you need to ensure before you start.

14. Make Your Own Barometer 

This experiment can help show kids how air pressure has an effect on the weather. The best way to do this is to build your own barometer! 

15. Create A Solar Oven

This is a quick and easy way to show students how radiant heat works. By harnessing its power, there are many things you can do! You just have to be careful.

16. The Sticky Ice Experiment 

It’s really fun to show students how salt has an effect on water and its freezing point. You need water, salt, and some string to carry this one out!

17. An Egg In A Bottle

Using a small bottle, some matches, and an egg, you can show your students how objects may react to adaptations in air pressure.

18. Make A CD Garden 

You’re certain to have some old CD cases around. If so, you can get kids involved in making their own CD case garden and observe the ways that plants grow!

19. The Gummy Worm Dance 

When an acidic liquid is mixed with a neutral solution, it’s possible for some things to react in hilarious ways that kids will love. Place a gummy worm in a jar and mix the solutions to watch your students laugh at the results.

20. Make A Green Penny 

If you have an old penny lying around, then why not test out this experiment , which takes about three days? It’s a cool way to learn about metal and chemical reactions , though! 

21. Soap Popcorn 

This experiment needs supervision from an adult, but it’s awesome to watch. Using Charles’ law, simply place a bar of soap in a microwave and watch how it expands as it heats up. 

22. The Cabbage PH Indicator 

Students can test out the PH levels of different liquids simply by using cabbage. It’s pretty simple to perform and it’s cool to watch.

23. Can Ice Grow?

This experiment needs to be followed step by step, but it’s really interesting to observe. With some basic steps, you can get your students to observe how ice might grow and form towers.

24. Paper Cup – The Strength In Numbers 

Using several paper cups and some cardboard sheets, this is an outdoor experiment that can help to demonstrate weight distribution and how paper cups can hold body weight when in numbers.

25. Separate Pepper And Salt 

Draw from the power of static electricity via a plastic spoon and show students how easy it is for matter to divide and separate – which can be shown with salt and pepper.

26. Fireworks In A Jar

At the right time of year, you can theme this experiment using oil, water, food coloring, and a jar. It’s a super fun project to help kids understand density – and the results are pretty! 

27. Water And Oil Discovery Bottles 

Most of us will be familiar with making water and oil discovery bottles from when we were kids, and it continues to be a super fun experiment for students today. All the bright colors are an awesome sensory experience for kids.

28. Color Mixing With Coffee Filters

This experiment is more for younger students, but it’s simple and effective. Using coffee filters, you can add liquids to watch how the filters absorb them and change colors, making mixes which make new colors.

29. Create Fizzy Lemonade 

A tasty experiment for the summer, this can help teach kids how mixing base liquids with acid creates a chemical reaction – but it results in something that you can enjoy at the end! 

30. Magic Milk 

This simple experiment needs a few items; milk, dish soap, and food coloring. This is a super colorful and fun thing to do and can help show kids how molecular behavior might work, how surface tension works, and a little bit about an object’s density.

31. Walking On Eggs 

Another experiment that can show the power of weight distribution is walking on eggs. Show your students how something so fragile can withstand body weight when in large numbers.

32. Create A Hydraulic Elevator 

This experiment sounds more complex than it actually is. You just need to use some sticks and large medicine droppers. It’s a classic experiment that many STEM teachers have used in the classroom before.

33. Demonstrate Inertia 

Newton’s first law of motion can be demonstrated pretty easily, and it’s never too early or too late to show students how it works! 

34. Grow Your Gummy Bears

When it comes to students and science, what better way to teach them than using candy ? Using all areas of the major sciences, you can turn little gummy bears into big gummy bears! 

35. The Disappearing Egg Shell

Students of all ages enjoy watching this experiment , and it’s helpful to show them the ways that chemical reactions operate.

36. Coca-Cola Tooth Experiment 

This is a classic experiment that can help show students the effects of sugary drinks on their teeth. When your students are young and losing their baby teeth, ask them to bring in a tooth and show them the horrible effects in a jar! 

37. Small Tornado In A Bottle

Most of us performed this experiment when we were students, and it’s super fun to keep it going with your own students. Demonstrating centripetal force by creating a water vortex in a bottle is awesome! 

38. Make A Bag Leak-Proof

Another experiment that demonstrates polymers, you need a plastic bag, some water, a sharp pencil, and some patience – and you can show kids the seemingly impossible!

39. Make A Non-Newtonian Fluid 

There are substances out there that get firmer when pressure is applied to them, and these are known as non-Newtonian fluids. It’s really intriguing to see how fluids can behave in such ways, so your students are bound to get a kick out of this.

40. Demonstrate Capillaries

You can show kids how our capillaries function using items you can find pretty much everywhere. It’s super cool and colorful and you’re bound to excite everyone with this in the classroom.

41. Make Candy Rock 

Students, candy, and rocks – they go hand in hand! Your students will love to create their own candy rock and watch as the rock crystals grow.

42. Make The Super Bubble

You can show students how to make a better version of bubble mixture to create much larger bubbles, called superbubbles! 

43. Frozen Vegetable Oil Paintings

Here’s another classic experiment that most kids have conducted when they were in the classroom. It’s a fun way to show kids how some liquids behave when they are frozen, and as vegetable oil behaves differently – you can make awesome paintings! 

44. Make An Ice Magnifying Glass 

This experiment is pretty simple, but we like to add something more fun to it. Once you have made your ice magnifying glass, show your students how glass behaves underwater by designing a real magnifying glass (do not allow them to do this though).

Glass under water can be cut and sliced in much different ways than above the surface, so you can easily create your own glass designs to show your students in a safe way.

45. Can Eggs Float?

Finally, on our list, we have the experiment that has shown students for years how eggs can float on water if salt is added to the liquid. It’s a simple way to explain density, and it’s always a good idea to bring in the Dead Sea example.

The Dead Sea is so salty that people can simply float on its surface, but it’s also deadly because if you turn around – it’s difficult to get your head out of the salty water! 

Things To Remember

There are always things you should remember when it comes to these sorts of experiments. Some are much more obvious than others, but it’s always important to ensure we’re on the same wavelength. These include the following.

Safety 

Conduct a health and safety risk assessment before you carry out any experiment, and always be aware of any safety equipment you and your students may need to wear. Be sure to take reasonable care with all of your experiments (and best to do a trial run first!).

Reinforce Learning 

It’s all fine and good demonstrating the experiments, but you must ensure that you reinforce the student’s learning by asking questions at the end of the lesson. It’s also wise to set some theoretical homework based on their practical experiment. 

Do Your Research 

It’s of course critical that you know exactly what you are doing before you show your students, but it’s also as important to know your students. For example, if an experiment is more tailored for younger students, do not try it for older kids.  You may also like: 1st grade science project ideas .

The Bottom Line 

And that’s our comprehensive list of the easiest science experiments that you can show students in the classroom, at home, or out in the field! We hope you have enjoyed our guide and you’ve found some amazing new experiments for your students! Good luck.

Top tip: Teach your students about the most famous inventors while they work on their own science experiments.

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15 Experimental Design Examples

Chris Drew (PhD)

Dr. Chris Drew is the founder of the Helpful Professor. He holds a PhD in education and has published over 20 articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education. [Image Descriptor: Photo of Chris]

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Experimental design involves testing an independent variable against a dependent variable. It is a central feature of the scientific method .

A simple example of an experimental design is a clinical trial, where research participants are placed into control and treatment groups in order to determine the degree to which an intervention in the treatment group is effective.

There are three categories of experimental design . They are:

• Pre-Experimental Design: Testing the effects of the independent variable on a single participant or a small group of participants (e.g. a case study).
• Quasi-Experimental Design: Testing the effects of the independent variable on a group of participants who aren’t randomly assigned to treatment and control groups (e.g. purposive sampling).
• True Experimental Design: Testing the effects of the independent variable on a group of participants who are randomly assigned to treatment and control groups in order to infer causality (e.g. clinical trials).

A good research student can look at a design’s methodology and correctly categorize it. Below are some typical examples of experimental designs, with their type indicated.

Experimental Design Examples

The following are examples of experimental design (with their type indicated).

1. Action Research in the Classroom

Type: Pre-Experimental Design

A teacher wants to know if a small group activity will help students learn how to conduct a survey. So, they test the activity out on a few of their classes and make careful observations regarding the outcome.

The teacher might observe that the students respond well to the activity and seem to be learning the material quickly.

However, because there was no comparison group of students that learned how to do a survey with a different methodology, the teacher cannot be certain that the activity is actually the best method for teaching that subject.

2. Study on the Impact of an Advertisement

An advertising firm has assigned two of their best staff to develop a quirky ad about eating a brand’s new breakfast product.

The team puts together an unusual skit that involves characters enjoying the breakfast while engaged in silly gestures and zany background music. The ad agency doesn’t want to spend a great deal of money on the ad just yet, so the commercial is shot with a low budget. The firm then shows the ad to a small group of people just to see their reactions.

Afterwards they determine that the ad had a strong impact on viewers so they move forward with a much larger budget.

3. Case Study

A medical doctor has a hunch that an old treatment regimen might be effective in treating a rare illness.

The treatment has never been used in this manner before. So, the doctor applies the treatment to two of their patients with the illness. After several weeks, the results seem to indicate that the treatment is not causing any change in the illness. The doctor concludes that there is no need to continue the treatment or conduct a larger study with a control condition.

4. Fertilizer and Plant Growth Study

An agricultural farmer is exploring different combinations of nutrients on plant growth, so she does a small experiment.

Instead of spending a lot of time and money applying the different mixes to acres of land and waiting several months to see the results, she decides to apply the fertilizer to some small plants in the lab.

After several weeks, it appears that the plants are responding well. They are growing rapidly and producing dense branching. She shows the plants to her colleagues and they all agree that further testing is needed under better controlled conditions .

5. Mood States Study

A team of psychologists is interested in studying how mood affects altruistic behavior. They are undecided however, on how to put the research participants in a bad mood, so they try a few pilot studies out.

They try one suggestion and make a 3-minute video that shows sad scenes from famous heart-wrenching movies.

They then recruit a few people to watch the clips and measure their mood states afterwards.

The results indicate that people were put in a negative mood, but since there was no control group, the researchers cannot be 100% confident in the clip’s effectiveness.

6. Math Games and Learning Study

Type: Quasi-Experimental Design

Two teachers have developed a set of math games that they think will make learning math more enjoyable for their students. They decide to test out the games on their classes.

So, for two weeks, one teacher has all of her students play the math games. The other teacher uses the standard teaching techniques. At the end of the two weeks, all students take the same math test. The results indicate that students that played the math games did better on the test.

Although the teachers would like to say the games were the cause of the improved performance, they cannot be 100% sure because the study lacked random assignment . There are many other differences between the groups that played the games and those that did not.

Learn More: Random Assignment Examples

7. Economic Impact of Policy

An economic policy institute has decided to test the effectiveness of a new policy on the development of small business. The institute identifies two cities in a third-world country for testing.

The two cities are similar in terms of size, economic output, and other characteristics. The city in which the new policy was implemented showed a much higher growth of small businesses than the other city.

Although the two cities were similar in many ways, the researchers must be cautious in their conclusions. There may exist other differences between the two cities that effected small business growth other than the policy.

8. Parenting Styles and Academic Performance

Psychologists want to understand how parenting style affects children’s academic performance.

So, they identify a large group of parents that have one of four parenting styles: authoritarian, authoritative, permissive, or neglectful. The researchers then compare the grades of each group and discover that children raised with the authoritative parenting style had better grades than the other three groups. Although these results may seem convincing, it turns out that parents that use the authoritative parenting style also have higher SES class and can afford to provide their children with more intellectually enriching activities like summer STEAM camps.

9. Movies and Donations Study

Will the type of movie a person watches affect the likelihood that they donate to a charitable cause? To answer this question, a researcher decides to solicit donations at the exit point of a large theatre.

He chooses to study two types of movies: action-hero and murder mystery. After collecting donations for one month, he tallies the results. Patrons that watched the action-hero movie donated more than those that watched the murder mystery. Can you think of why these results could be due to something other than the movie?

10. Gender and Mindfulness Apps Study

Researchers decide to conduct a study on whether men or women benefit from mindfulness the most. So, they recruit office workers in large corporations at all levels of management.

Then, they divide the research sample up into males and females and ask the participants to use a mindfulness app once each day for at least 15 minutes.

At the end of three weeks, the researchers give all the participants a questionnaire that measures stress and also take swabs from their saliva to measure stress hormones.

The results indicate the women responded much better to the apps than males and showed lower stress levels on both measures.

Unfortunately, it is difficult to conclude that women respond to apps better than men because the researchers could not randomly assign participants to gender. This means that there may be extraneous variables that are causing the results.

11. Eyewitness Testimony Study

Type: True Experimental Design

To study the how leading questions on the memories of eyewitnesses leads to retroactive inference , Loftus and Palmer (1974) conducted a simple experiment consistent with true experimental design.

Research participants all watched the same short video of two cars having an accident. Each were randomly assigned to be asked either one of two versions of a question regarding the accident.

Half of the participants were asked the question “How fast were the two cars going when they smashed into each other?” and the other half were asked “How fast were the two cars going when they contacted each other?”

Participants’ estimates were affected by the wording of the question. Participants that responded to the question with the word “smashed” gave much higher estimates than participants that responded to the word “contacted.”

12. Sports Nutrition Bars Study

A company wants to test the effects of their sports nutrition bars. So, they recruited students on a college campus to participate in their study. The students were randomly assigned to either the treatment condition or control condition.

Participants in the treatment condition ate two nutrition bars. Participants in the control condition ate two similar looking bars that tasted nearly identical, but offered no nutritional value.

One hour after consuming the bars, participants ran on a treadmill at a moderate pace for 15 minutes. The researchers recorded their speed, breathing rates, and level of exhaustion.

The results indicated that participants that ate the nutrition bars ran faster, breathed more easily, and reported feeling less exhausted than participants that ate the non-nutritious bar.

13. Clinical Trials

Medical researchers often use true experiments to assess the effectiveness of various treatment regimens. For a simplified example: people from the population are randomly selected to participate in a study on the effects of a medication on heart disease.

Participants are randomly assigned to either receive the medication or nothing at all. Three months later, all participants are contacted and they are given a full battery of heart disease tests.

The results indicate that participants that received the medication had significantly lower levels of heart disease than participants that received no medication.

14. Leadership Training Study

A large corporation wants to improve the leadership skills of its mid-level managers. The HR department has developed two programs, one online and the other in-person in small classes.

HR randomly selects 120 employees to participate and then randomly assigned them to one of three conditions: one-third are assigned to the online program, one-third to the in-class version, and one-third are put on a waiting list.

The training lasts for 6 weeks and 4 months later, supervisors of the participants are asked to rate their staff in terms of leadership potential. The supervisors were not informed about which of their staff participated in the program.

The results indicated that the in-person participants received the highest ratings from their supervisors. The online class participants came in second, followed by those on the waiting list.

15. Reading Comprehension and Lighting Study

Different wavelengths of light may affect cognitive processing. To put this hypothesis to the test, a researcher randomly assigned students on a college campus to read a history chapter in one of three lighting conditions: natural sunlight, artificial yellow light, and standard fluorescent light.

At the end of the chapter all students took the same exam. The researcher then compared the scores on the exam for students in each condition. The results revealed that natural sunlight produced the best test scores, followed by yellow light and fluorescent light.

Therefore, the researcher concludes that natural sunlight improves reading comprehension.

See Also: Experimental Study vs Observational Study

Experimental design is a central feature of scientific research. When done using true experimental design, causality can be infered, which allows researchers to provide proof that an independent variable affects a dependent variable. This is necessary in just about every field of research, and especially in medical sciences.

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Cool Science Experiments Headquarters

Making Science Fun, Easy to Teach and Exciting to Learn!

Science Experiments

35 Easy Science Experiments You Can Do Today!

Looking for easy science experiments to do at home or in the classroom? You’re in luck because we’ve got over 35 easy science activities for kids that will help you make science fun for all ages. 

Most of these simple science experiments for kids are easy to prepare, quick to perform, and use household items or inexpensive materials you can find almost anywhere. To connect the fun to the “why it works” you’ll find an easy to teach explanation with every experiment!

Musical Jars Science Experiment 

This super easy experiment is simple as it is fun! Kids make their own musical instruments with clear jars and water then investigate sound waves, pitch, and more.

When the experiment is complete, use the colorful new “instrument” for a fun music lesson. Kids can play and take turns to “name that tune”!

Detailed Instructions & Video Tutorial ->  Musical Jars Science Experiment

Viscosity of Liquids Science Experiment

Viscosity may be a confusing term for kids at first, but this super easy experiment can help them see viscosity in action!

With marbles, clear jars, and a few household materials, kids will make predictions, record data, and compare the results while they test high and low density liquids.

Detailed Instructions & Video Tutorial ->   Viscosity Science Experiment

Floating Egg Science Experiment

Can a solid egg float? Kids can find the answer and understand why with this quick science experiment. 

Discover just how easy it can be to make a raw egg float while testing the laws of density. We’ve included additional ideas to try so kids can make predictions and test the concept further.

Detailed Instructions & Video Tutorial ->   Floating Egg Science Experiment

Paper Towel Dry Under Water Experiment

Is it possible to keep a paper towel dry even when submerging it under water? The answer is a surprising “yes,” if you use science to help!

Start with the properties of your materials, make a prediction, then explore matter, density, volume, and more.

Detailed Instructions & Video Tutorial ->   Paper Towel Dry Under Water Experiment

Mixing Oil & Water Science Experiment

This simple experiment for kids helps them better understand density and the changes that happen when adding an emulsifier to the mix. 

Detailed Instructions & Video Tutorial ->   Mixing Oil & Water Experiment

Will it Float or Sink Science Experiment

Will it sink or will it float? This fun experiment challenges what students think they know about household items!

Students record their hypothesis for each item then test it to compare what they think will happen against their observations.

Detailed Instructions & Video Tutorial -> Float or Sink Science Experiment

Water Temperature Science Experiment

What does thermal energy look like? In this easy science experiment, kids are able to see thermal energy as they explore the concept in action.

With clear jars and food coloring, students can quickly see how molecules move differently through hot and cold water.

Detailed Instructions & Video Tutorial -> Water Temperature Science Experiment

Balloon Blow-up Science Experiment

Kids will discover how matter reacts when heated and cooled as they watch with surprise as baking soda and vinegar blow the balloon up before their eyes.

Detailed Instructions & Video Tutorial -> Balloon Blow-up Science Experiment

Floating Ping Pong Ball Science Experiment

Kids will giggle with joy with this super easy experiment. With only a ping pong ball and a hair dryer, students will have a great time while exploring Bernoulli’s Principle in action. 

We’ve included additional ideas to further explore the concept with different objects and observe the change in results.

Detailed Instructions & Video Tutorial -> Floating Ping Pong Ball Science Experiment

Hair Stand on End Science Experiment

It’s especially fun for those who’ve never seen static electricity in action before!

Detailed Instructions & Video Tutorial -> Hair Stand on End Science Experiment

Oil Bubbles in Water Science Experiment

Kids explore density and experience some chemistry when creating oil bubbles in water with everyday household items.

This experiment is particularly fun when kids see that they’ve made what looks like a lava lamp!

Detailed Instructions & Video Tutorial ->  Oil Bubbles in Water Science Experiment

Color Changing Water Science Experiment

Kids will be surprised as they watch a new color being “created” without mixing! Using only a clear bowl and glass, some food coloring, and water, this super easy science experiment is quick and easy with a huge wow factor. 

Try it with yellow and blue to follow along with our demonstration video then try different primary color combinations and explore the results.

Detailed Instructions & Video Tutorial ->  Color Changing Water Science Experiment

Magnetic Paper Clip Chain Science Experiment

It may seem a bit like magic but it’s actually science! It’s not hard to capture your kids’ attention with this quick and easy science experiment as they watch paper clips “stick” together and form a chain!

Perfect for younger children, the experiment only takes a few minutes and is a fun way to explore the concept of magnetic transference.

Detailed Instructions & Video Tutorial ->  Magnetic Paper Clip Chain Science Experiment

Is it Magnetic Science Experiment

With only a magnet and a few household items, kids will make and record their predictions, test and observe, then compare what they think is magnetic against the results.

Simple and quick, but some of the results may surprise your students!

Cloud in a Jar Experiment

This simple experiment only requires a few materials but really holds student attention as a cloud forms before their eyes!

Kids will learn new weather vocabulary as they explore how physical changes and reactions happen as clouds begin to take form. We’ve also included a helpful chart on the types of clouds.

Detailed Instructions & Video Tutorial ->  Cloud in a Jar Science Experiment

Magic Milk Science Experiment

Create a dancing rainbow of colors with this easy science experiment for kids!

Using only a few ordinary kitchen items, your students can create a color explosion in ordinary milk when they add our special ingredient. (Hint: The special ingredient (soap!) includes hydrophilic and hydrophobic molecules that make the magic happen!)

Detailed Instructions & Video Tutorial ->  Magic Milk Science Experiment

Walking Water Science Experiment

Water can’t really walk upwards against gravity, but this cool science experiment makes it seem like it can! 

Kids are able to see the capillary action process and learn how attraction and adhesive forces in action allow water to move out of one glass into another. 

Detailed Instructions & Video Tutorial -> Walking Water Science Experiment

Light Refraction Science Experiment

The results of this easy science experiment are so amazing, it makes kids (and adults) think it must be magic!

Young scientists watch in surprise while they see an arrow change directions instantly. Investigating refraction couldn’t be more fun!

Detailed Instructions & Video Tutorial -> Light Refraction Science Experiment

Dancing Raisins Experiment

Learn about the reactions of buoyancy and density in this simple science activity for kids. 

They may not need dancing shoes, but give them a glass of soda pop and the raisins in this fun experiment love to dance!

Detailed Instructions & Video Tutorial -> Dancing Raisins Science Experiment

See Sound Experiment

Kids love this experiment because they are encouraged to drum loudly so they can “see” sound waves in action!

Detailed Instructions & Video Tutorial -> See Sound Science Experiment

Elephant Toothpaste Science Experiment

Grab some giant brushes and get ready to make elephant toothpaste! Although you might not be able to get an elephant excited by this super easy experiment, kids love it!

The impressive and quick results created by the chemical reaction and the heat released in the process makes an abundant amount of fun and colorful foam!

Detailed Instructions & Video Tutorial -> Elephant Toothpaste Science Experiment

Upside Down Glass of Water Science Experiment

We all know what happens when we turn a glass of water upside down, but what if I told you you can do it without the water spilling out?

The experiment only requires a few common items and you’ll be amazed by the results of air pressure in action!

Detailed Instructions & Video Tutorial -> Upside Down Glass of Water Science Experiment

Pick up Ball with a Jar Science Experiment

It almost seems like magic but with the help of science, you can pick up a ball with an open jar!

Instead of magic, this easy science activity uses centripetal force and practice to do what seems like the impossible. 

Detailed Instructions & Video Tutorial -> Pick up Ball with a Jar Experiment

Will It Melt Science Experiment

Can you guess which items will melt? This easy outside experiment challenges what students think they know about the effects of the sun.

Pepper Move Science Experiment

Can you make pepper move and zoom away with just a light touch of your finger? With science you can!

This experiment only takes a few quick minutes from beginning to end, but the reaction caused by surface tension makes kids want to do it over and over. 

Detailed Instructions & Video Tutorial ->  Pepper Move Science Experiment

Crush a Plastic Bottle Science Experiment

Go for it, crush that bottle, but don’t touch it! Although it usually can’t be seen or touched, air pressure is pushing against all surfaces at all times.

With this easy science activity kids can see air pressure at work when they watch a bottle crushes itself!

Detailed Instructions & Video Tutorial -> Crush a Plastic Bottle Science Experiment

Egg in Vinegar Science Experiment

This vinegar science experiment will have your eggs and kids bouncing (with excitement!) before you know it!

Kids can watch and explore the results of chemical reactions as the egg changes from something that seems solid into what feels like something bouncy!

Detailed Instructions & Video Tutorial -> Egg in Vinegar Science Experiment

Straw Through a Potato Science Experiment

Can you make a normal plastic straw go into a raw, solid potato? It seems like something impossible, but science can easily make it possible!

Pick your potatoes then let kids try their strength as they explore air pressure with this super easy experiment.

Detailed Instructions & Video Tutorial -> Straw Through a Potato Science Experiment

Rainbow in a Jar Science Experiment

With only a few household items, they’ll explore mass, volume, and density with every color layer!

Detailed Instructions & Video Tutorial -> Rainbow in a Jar Experiment

Tornado in a Bottle Science Experiment

Kids can have fun while learning more about centripetal force with this fun experiment.

With a little muscle and science, kids watch with amazement as they create their own glitter cyclone in a bottle as the centripetal force vortex appears.

Detailed Instructions & Video Tutorial -> Tornado in a Bottle Science Experiment

Why Doesn’t the Water Leak Science Experiment

Can you poke holes in a plastic bag full of water without the water leaking out? With this super easy science activity you can!

Kids are stunned as they learn about polymers and how they can do what seems to be impossible.

Detailed Instructions & Video Tutorial -> Why Doesn’t the Water Leak Science Experiment

Use a Bottle to Blow-up a Balloon Experiment

Is it possible to blow up a balloon with only water and science? 

In this super easy experiment, kids learn more about how matter behaves as they watch a balloon inflate and deflate as a result of matter being heated and cooled.

Detailed Instructions & Video Tutorial -> Use a Bottle to Blow-up a Balloon Experiment

Orange Float Science Experiment

Kids explore buoyancy as they learn about and test density in this sink or float science activity.

While it only takes a few minutes, this super easy experiment invites kids to predict what they think will happen then discuss why the heavier orange floats!

Detailed Instructions & Video Tutorial -> Orange Float Science Experiment

Pick up Ice with String Science Experiment

With only a few household items, kids learn about freezing temperatures and the results they create in saltwater versus freshwater.

Detailed Instructions & Video Tutorial -> Pick Up Ice with String Science Experiment

Color Changing Walking Water Experiment

Using the concepts explored in our popular Walking Water Science Experiment, kids will see color walk from one glass to another and change colors as it goes!

The quick experiment seems to defy gravity like magic, but don’t worry, kids can find out how science makes it work!

Detailed Instructions & Video Tutorial -> Color Changing Walking Water Experiment

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11+ Psychology Experiment Ideas (Goals + Methods)

Have you ever wondered why some days you remember things easily, while on others you keep forgetting? Or why certain songs make you super happy and others just…meh?

Our minds are like big, mysterious puzzles, and every day we're finding new pieces to fit. One of the coolest ways to explore our brains and the way they work is through psychology experiments.

A psychology experiment is a special kind of test or activity researchers use to learn more about how our minds work and why we behave the way we do.

It's like a detective game where scientists ask questions and try out different clues to find answers about our feelings, thoughts, and actions. These experiments aren't just for scientists in white coats but can be fun activities we all try to discover more about ourselves and others.

Some of these experiments have become so famous, they’re like the celebrities of the science world! Like the Marshmallow Test, where kids had to wait to eat a yummy marshmallow, or Pavlov's Dogs, where dogs learned to drool just hearing a bell.

Let's look at a few examples of psychology experiments you can do at home.

What Are Some Classic Experiments?

Imagine a time when the mysteries of the mind were being uncovered in groundbreaking ways. During these moments, a few experiments became legendary, capturing the world's attention with their intriguing results.

The Marshmallow Test

One of the most talked-about experiments of the 20th century was the Marshmallow Test , conducted by Walter Mischel in the late 1960s at Stanford University.

The goal was simple but profound: to understand a child's ability to delay gratification and exercise self-control.

Children were placed in a room with a marshmallow and given a choice: eat the marshmallow now or wait 15 minutes and receive two as a reward. Many kids struggled with the wait, some devouring the treat immediately, while others demonstrated remarkable patience.

But the experiment didn’t end there. Years later, Mischel discovered something astonishing. The children who had waited for the second marshmallow were generally more successful in several areas of life, from school achievements to job satisfaction!

While this experiment highlighted the importance of teaching patience and self-control from a young age, it wasn't without its criticisms. Some argued that a child's background, upbringing, or immediate surroundings might play a significant role in their choices.

Moreover, there were concerns about the ethics of judging a child's potential success based on a brief interaction with a marshmallow.

Pavlov's Dogs

Traveling further back in time and over to Russia, another classic experiment took the world by storm. Ivan Pavlov , in the early 1900s, wasn't initially studying learning or behavior. He was exploring the digestive systems of dogs.

But during his research, Pavlov stumbled upon a fascinating discovery. He noticed that by ringing a bell every time he fed his dogs, they eventually began to associate the bell's sound with mealtime. So much so, that merely ringing the bell, even without presenting food, made the dogs drool in anticipation!

This reaction demonstrated the concept of "conditioning" - where behaviors can be learned by linking two unrelated stimuli. Pavlov's work revolutionized the world's understanding of learning and had ripple effects in various areas like animal training and therapy techniques.

Pavlov came up with the term classical conditioning , which is still used today. Other psychologists have developed more nuanced types of conditioning that help us understand how people learn to perform different behaviours.

Classical conditioning is the process by which a neutral stimulus becomes associated with a meaningful stimulus , leading to the same response. In Pavlov's case, the neutral stimulus (bell) became associated with the meaningful stimulus (food), leading the dogs to salivate just by hearing the bell.

Modern thinkers often critique Pavlov's methods from an ethical standpoint. The dogs, crucial to his discovery, may not have been treated with today's standards of care and respect in research.

Both these experiments, while enlightening, also underline the importance of conducting research with empathy and consideration, especially when it involves living beings.

What is Ethical Experimentation?

The tales of Pavlov's bells and Mischel's marshmallows offer us not just insights into the human mind and behavior but also raise a significant question: At what cost do these discoveries come?

Ethical experimentation isn't just a fancy term; it's the backbone of good science. When we talk about ethics, we're referring to the moral principles that guide a researcher's decisions and actions. But why does it matter so much in the realm of psychological experimentation?

An example of an experiment that had major ethical issues is an experiment called the Monster Study . This study was conducted in 1936 and was interested in why children develop a stutter.

The major issue with it is that the psychologists treated some of the children poorly over a period of five months, telling them things like “You must try to stop yourself immediately. Don’t ever speak unless you can do it right.”

You can imagine how that made the children feel!

This study helped create guidelines for ethical treatment in experiments. The guidelines include:

Respect for Individuals: Whether it's a dog in Pavlov's lab or a child in Mischel's study room, every participant—human or animal—deserves respect. They should never be subjected to harm or undue stress. For humans, informed consent (knowing what they're signing up for) is a must. This means that if a child is participating, they, along with their guardians, should understand what the experiment entails and agree to it without being pressured.

Honesty is the Best Policy: Researchers have a responsibility to be truthful. This means not only being honest with participants about the study but also reporting findings truthfully, even if the results aren't what they hoped for. There can be exceptions if an experiment will only succeed if the participants aren't fully aware, but it has to be approved by an ethics committee .

Safety First: No discovery, no matter how groundbreaking, is worth harming a participant. The well-being and mental, emotional, and physical safety of participants is paramount. Experiments should be designed to minimize risks and discomfort.

Considering the Long-Term: Some experiments might have effects that aren't immediately obvious. For example, while a child might seem fine after participating in an experiment, they could feel stressed or anxious later on. Ethical researchers consider and plan for these possibilities, offering support and follow-up if needed.

The Rights of Animals: Just because animals can't voice their rights doesn't mean they don't have any. They should be treated with care, dignity, and respect. This means providing them with appropriate living conditions, not subjecting them to undue harm, and considering alternatives to animal testing when possible.

While the world of psychological experiments offers fascinating insights into behavior and the mind, it's essential to tread with care and compassion. The golden rule? Treat every participant, human or animal, as you'd wish to be treated. After all, the true mark of a groundbreaking experiment isn't just its findings but the ethical integrity with which it's conducted.

So, even if you're experimenting at home, please keep in mind the impact your experiments could have on the people and beings around you!

Let's get into some ideas for experiments.

1) Testing Conformity

Our primary aim with this experiment is to explore the intriguing world of social influences, specifically focusing on how much sway a group has over an individual's decisions. This social influence is called groupthink .

Humans, as social creatures, often find solace in numbers, seeking the approval and acceptance of those around them. But how deep does this need run? Does the desire to "fit in" overpower our trust in our own judgments?

This experiment not only provides insights into these questions but also touches upon the broader themes of peer pressure, societal norms, and individuality. Understanding this could shed light on various real-world situations, from why fashion trends catch on to more critical scenarios like how misinformation can spread.

Method: This idea is inspired by the classic Asch Conformity Experiments . Here's a simple way to try it:

• Assemble a group of people (about 7-8). Only one person will be the real participant; the others will be in on the experiment.
• Show the group a picture of three lines of different lengths and another line labeled "Test Line."
• Ask each person to say out loud which of the three lines matches the length of the "Test Line."
• Unknown to the real participant, the other members will intentionally choose the wrong line. This is to see if the participant goes along with the group's incorrect choice, even if they can see it's wrong.

Real-World Impacts of Groupthink

Groupthink is more than just a science term; we see it in our daily lives:

Decisions at Work or School: Imagine being in a group where everyone wants to do one thing, even if it's not the best idea. People might not speak up because they're worried about standing out or being the only one with a different opinion.

Wrong Information: Ever heard a rumor that turned out to be untrue? Sometimes, if many people believe and share something, others might believe it too, even if it's not correct. This happens a lot on the internet.

Peer Pressure: Sometimes, friends might all want to do something that's not safe or right. People might join in just because they don't want to feel left out.

Missing Out on New Ideas: When everyone thinks the same way and agrees all the time, cool new ideas might never get heard. It's like always coloring with the same crayon and missing out on all the other bright colors!

2) Testing Color and Mood

We all have favorite colors, right? But did you ever wonder if colors can make you feel a certain way? Color psychology is the study of how colors can influence our feelings and actions.

For instance, does blue always calm us down? Does red make us feel excited or even a bit angry? By exploring this, we can learn how colors play a role in our daily lives, from the clothes we wear to the color of our bedroom walls.

• Find a quiet room and set up different colored lights or large sheets of colored paper: blue, red, yellow, and green.
• Invite some friends over and let each person spend a few minutes under each colored light or in front of each colored paper.
• After each color, ask your friends to write down or talk about how they feel. Are they relaxed? Energized? Happy? Sad?

Researchers have always been curious about this. Some studies have shown that colors like blue and green can make people feel calm, while colors like red might make them feel more alert or even hungry!

Real-World Impacts of Color Psychology

Ever noticed how different places use colors?

Hospitals and doctors' clinics often use soft blues and greens. This might be to help patients feel more relaxed and calm.

Many fast food restaurants use bright reds and yellows. These colors might make us feel hungry or want to eat quickly and leave.

Classrooms might use a mix of colors to help students feel both calm and energized.

3) Testing Music and Brainpower

Think about your favorite song. Do you feel smarter or more focused when you listen to it? This experiment seeks to understand the relationship between music and our brain's ability to remember things. Some people believe that certain types of music, like classical tunes, can help us study or work better. Let's find out if it's true!

• Prepare a list of 10-15 things to remember, like a grocery list or names of places.
• Invite some friends over. First, let them try to memorize the list in a quiet room.
• After a short break, play some music (try different types like pop, classical, or even nature sounds) and ask them to memorize the list again.
• Compare the results. Was there a difference in how much they remembered with and without music?

The " Mozart Effect " is a popular idea. Some studies in the past suggested that listening to Mozart's music might make people smarter, at least for a little while. But other researchers think the effect might not be specific to Mozart; it could be that any music we enjoy boosts our mood and helps our brain work better.

Real-World Impacts of Music and Memory

Think about how we use music:

• Study Sessions: Many students listen to music while studying, believing it helps them concentrate better.
• Workout Playlists: Gyms play energetic music to keep people motivated and help them push through tough workouts.
• Meditation and Relaxation: Calm, soothing sounds are often used to help people relax or meditate.

4) Testing Dreams and Food

Ever had a really wild dream and wondered where it came from? Some say that eating certain foods before bedtime can make our dreams more vivid or even a bit strange.

This experiment is all about diving into the dreamy world of sleep to see if what we eat can really change our nighttime adventures. Can a piece of chocolate or a slice of cheese transport us to a land of wacky dreams? Let's find out!

• Ask a group of friends to keep a "dream diary" for a week. Every morning, they should write down what they remember about their dreams.
• For the next week, ask them to eat a small snack before bed, like cheese, chocolate, or even spicy foods.
• They should continue writing in their "dream diary" every morning.
• At the end of the two weeks, compare the dream notes. Do the dreams seem different during the snack week?

The link between food and dreams isn't super clear, but some people have shared personal stories. For example, some say that spicy food can lead to bizarre dreams. Scientists aren't completely sure why, but it could be related to how food affects our body temperature or brain activity during sleep.

A cool idea related to this experiment is that of vivid dreams , which are very clear, detailed, and easy to remember dreams. Some people are even able to control their vivid dreams, or say that they feel as real as daily, waking life !

Real-World Impacts of Food and Dreams

Our discoveries might shed light on:

• Bedtime Routines: Knowing which foods might affect our dreams can help us choose better snacks before bedtime, especially if we want calmer sleep.
• Understanding Our Brain: Dreams can be mysterious, but studying them can give us clues about how our brains work at night.
• Cultural Beliefs: Many cultures have myths or stories about foods and dreams. Our findings might add a fun twist to these age-old tales!

5) Testing Mirrors and Self-image

Stand in front of a mirror. How do you feel? Proud? Shy? Curious? Mirrors reflect more than just our appearance; they might influence how we think about ourselves.

This experiment delves into the mystery of self-perception. Do we feel more confident when we see our reflection? Or do we become more self-conscious? Let's take a closer look.

• Set up two rooms: one with mirrors on all walls and another with no mirrors at all.
• Invite friends over and ask them to spend some time in each room doing normal activities, like reading or talking.
• After their time in both rooms, ask them questions like: "Did you think about how you looked more in one room? Did you feel more confident or shy?"
• Compare the responses to see if the presence of mirrors changes how they feel about themselves.

Studies have shown that when people are in rooms with mirrors, they can become more aware of themselves. Some might stand straighter, fix their hair, or even change how they behave. The mirror acts like an audience, making us more conscious of our actions.

Real-World Impacts of Mirrors and Self-perception

Mirrors aren't just for checking our hair. Ever wonder why clothing stores have so many mirrors? They might help shoppers visualize themselves in new outfits, encouraging them to buy.

Mirrors in gyms can motivate people to work out with correct form and posture. They also help us see progress in real-time!

And sometimes, looking in a mirror can be a reminder to take care of ourselves, both inside and out.

But remember, what we look like isn't as important as how we act in the world or how healthy we are. Some people claim that having too many mirrors around can actually make us more self conscious and distract us from the good parts of ourselves.

Some studies are showing that mirrors can actually increase self-compassion , amongst other things. As any tool, it seems like mirrors can be both good and bad, depending on how we use them!

6) Testing Plants and Talking

Have you ever seen someone talking to their plants? It might sound silly, but some people believe that plants can "feel" our vibes and that talking to them might even help them grow better.

In this experiment, we'll explore whether plants can indeed react to our voices and if they might grow taller, faster, or healthier when we chat with them.

• Get three similar plants, placing each one in a separate room.
• Talk to the first plant, saying positive things like "You're doing great!" or singing to it.
• Say negative things to the second plant, like "You're not growing fast enough!"
• Don't talk to the third plant at all; let it be your "silent" control group .
• Water all plants equally and make sure they all get the same amount of light.
• At the end of the month, measure the growth of each plant and note any differences in their health or size.

The idea isn't brand new. Some experiments from the past suggest plants might respond to sounds or vibrations. Some growers play music for their crops, thinking it helps them flourish.

Even if talking to our plants doesn't have an impact on their growth, it can make us feel better! Sometimes, if we are lonely, talking to our plants can help us feel less alone. Remember, they are living too!

Real-World Impacts of Talking to Plants

If plants do react to our voices, gardeners and farmers might adopt new techniques, like playing music in greenhouses or regularly talking to plants.

Taking care of plants and talking to them could become a recommended activity for reducing stress and boosting mood.

And if plants react to sound, it gives us a whole new perspective on how connected all living things might be .

7) Testing Virtual Reality and Senses

Virtual reality (VR) seems like magic, doesn't it? You put on a headset and suddenly, you're in a different world! But how does this "new world" affect our senses? This experiment wants to find out how our brains react to VR compared to the real world. Do we feel, see, or hear things differently? Let's get to the bottom of this digital mystery!

• You'll need a VR headset and a game or experience that can be replicated in real life (like walking through a forest). If you don't have a headset yourself, there are virtual reality arcades now!
• Invite friends to first experience the scenario in VR.
• Afterwards, replicate the experience in the real world, like taking a walk in an actual forest.
• Ask them questions about both experiences: Did one seem more real than the other? Which sounds were more clear? Which colors were brighter? Did they feel different emotions?

As VR becomes more popular, scientists have been curious about its effects. Some studies show that our brains can sometimes struggle to tell the difference between VR and reality. That's why some people might feel like they're really "falling" in a VR game even though they're standing still.

Real-World Impacts of VR on Our Senses

Schools might use VR to teach lessons, like taking students on a virtual trip to ancient Egypt. Understanding how our senses react in VR can also help game designers create even more exciting and realistic games.

Doctors could use VR to help patients overcome fears or to provide relaxation exercises. This is actually already a method therapists can use for helping patients who have serious phobias. This is called exposure therapy , which basically means slowly exposing someone (or yourself) to the thing you fear, starting from very far away to becoming closer.

For instance, if someone is afraid of snakes. You might show them images of snakes first. Once they are comfortable with the picture, they can know there is one in the next room. Once they are okay with that, they might use a VR headset to see the snake in the same room with them, though of course there is not an actual snake there.

8) Testing Sleep and Learning

We all know that feeling of trying to study or work when we're super tired. Our brains feel foggy, and it's hard to remember stuff. But how exactly does sleep (or lack of it) influence our ability to learn and remember things?

With this experiment, we'll uncover the mysteries of sleep and see how it can be our secret weapon for better learning.

• Split participants into two groups.
• Ask both groups to study the same material in the evening.
• One group goes to bed early, while the other stays up late.
• The next morning, give both groups a quiz on what they studied.
• Compare the results to see which group remembered more.

Sleep and its relation to learning have been explored a lot. Scientists believe that during sleep, especially deep sleep, our brains sort and store new information. This is why sometimes, after a good night's rest, we might understand something better or remember more.

Real-World Impacts of Sleep and Learning

Understanding the power of sleep can help:

• Students: If they know the importance of sleep, students might plan better, mixing study sessions with rest, especially before big exams.
• Workplaces: Employers might consider more flexible hours, understanding that well-rested employees learn faster and make fewer mistakes.
• Health: Regularly missing out on sleep can have other bad effects on our health. So, promoting good sleep is about more than just better learning.

9) Testing Social Media and Mood

Have you ever felt different after spending time on social media? Maybe happy after seeing a friend's fun photos, or a bit sad after reading someone's tough news.

Social media is a big part of our lives, but how does it really affect our mood? This experiment aims to shine a light on the emotional roller-coaster of likes, shares, and comments.

• Ask participants to note down how they're feeling - are they happy, sad, excited, or bored?
• Have them spend a set amount of time (like 30 minutes) on their favorite social media platforms.
• After the session, ask them again about their mood. Did it change? Why?
• Discuss what they saw or read that made them feel that way.

Previous research has shown mixed results. Some studies suggest that seeing positive posts can make us feel good, while others say that too much time on social media can make us feel lonely or left out.

Real-World Impacts of Social Media on Mood

Understanding the emotional impact of social media can help users understand their feelings and take breaks if needed. Knowing is half the battle! Additionally, teachers and parents can guide young users on healthy social media habits, like limiting time or following positive accounts.

And if it's shown that social media does impact mood, social media companies can design friendlier, less stressful user experiences.

But even if the social media companies don't change things, we can still change our social media habits to make ourselves feel better.

10) Testing Handwriting or Typing

Think about the last time you took notes. Did you grab a pen and paper or did you type them out on a computer or tablet?

Both ways are popular, but there's a big question: which method helps us remember and understand better? In this experiment, we'll find out if the classic art of handwriting has an edge over speedy typing.

• Divide participants into two groups.
• Present a short lesson or story to both groups.
• One group will take notes by hand, while the other will type them out.
• After some time, quiz both groups on the content of the lesson or story.
• Compare the results to see which note-taking method led to better recall and understanding.

Studies have shown some interesting results. While typing can be faster and allows for more notes, handwriting might boost memory and comprehension because it engages the brain differently, making us process the information as we write.

Importantly, each person might find one or the other works better for them. This could be useful in understanding our learning habits and what instructional style would be best for us.

Real-World Impacts of Handwriting vs. Typing

Knowing the pros and cons of each method can:

• Boost Study Habits: Students can pick the method that helps them learn best, especially during important study sessions or lectures.
• Work Efficiency: In jobs where information retention is crucial, understanding the best method can increase efficiency and accuracy.
• Tech Design: If we find out more about how handwriting benefits us, tech companies might design gadgets that mimic the feel of writing while combining the advantages of digital tools.

11) Testing Money and Happiness

We often hear the saying, "Money can't buy happiness," but is that really true? Many dream of winning the lottery or getting a big raise, believing it would solve all problems.

In this experiment, we dig deep to see if there's a real connection between wealth and well-being.

• Survey a range of participants, from those who earn a little to those who earn a lot, about their overall happiness. You can keep it to your friends and family, but that might not be as accurate as surveying a wider group of people.
• Ask them to rank things that bring them joy and note if they believe more money would boost their happiness. You could try different methods, one where you include some things that they have to rank, such as gardening, spending time with friends, reading books, learning, etc. Or you could just leave a blank list that they can fill in with their own ideas.
• Study the data to find patterns or trends about income and happiness.

Some studies have found money can boost happiness, especially when it helps people out of tough financial spots. But after reaching a certain income, extra dollars usually do not add much extra joy.

In fact, psychologists just realized that once people have an income that can comfortably support their needs (and some of their wants), they stop getting happier with more . That number is roughly $75,000, but of course that depends on the cost of living and how many members are in the family.

Real-World Impacts of Money and Happiness

If we can understand the link between money and joy, it might help folks choose jobs they love over jobs that just pay well. And instead of buying things, people might spend on experiences, like trips or classes, that make lasting memories.

Most importantly, we all might spend more time on hobbies, friends, and family, knowing they're big parts of what makes life great.

Some people are hoping that with Artificial Intelligence being able to do a lot of the less well-paying jobs, people might be able to do work they enjoy more, all while making more money and having more time to do the things that make them happy.

12) Testing Temperature and Productivity

Have you ever noticed how a cold classroom or office makes it harder to focus? Or how on hot days, all you want to do is relax? In this experiment, we're going to find out if the temperature around us really does change how well we work.

• Find a group of participants and a room where you can change the temperature.
• Set the room to a chilly temperature and give the participants a set of tasks to do.
• Measure how well and quickly they do these tasks.
• The next day, make the room comfortably warm and have them do similar tasks.
• Compare the results to see if the warmer or cooler temperature made them work better.

Some studies have shown that people can work better when they're in a room that feels just right, not too cold or hot. Being too chilly can make fingers slow, and being too warm can make minds wander.

What temperature is "just right"? It won't be the same for everyone, but most people find it's between 70-73 degrees Fahrenheit (21-23 Celsius).

Real-World Implications of Temperature and Productivity

If we can learn more about how temperature affects our work, teachers might set classroom temperatures to help students focus and learn better, offices might adjust temperatures to get the best work out of their teams, and at home, we might find the best temperature for doing homework or chores quickly and well.

Interestingly, temperature also has an impact on our sleep quality. Most people find slightly cooler rooms to be better for good sleep. While the daytime temperature between 70-73F is good for productivity, a nighttime temperature around 65F (18C) is ideal for most people's sleep.

Psychology is like a treasure hunt, where the prize is understanding ourselves better. With every experiment, we learn a little more about why we think, feel, and act the way we do. Some of these experiments might seem simple, like seeing if colors change our mood or if being warm helps us work better. But even the simple questions can have big answers that help us in everyday life.

Remember, while doing experiments is fun, it's also important to always be kind and think about how others feel. We should never make someone uncomfortable just for a test. Instead, let's use these experiments to learn and grow, helping to make the world a brighter, more understanding place for everyone.

Related posts:

• 150+ Flirty Goodnight Texts For Him (Sweet and Naughty Examples)
• Dream Interpreter & Dictionary (270+ Meanings)
• Sleep Stages (Light, Deep, REM)
• What Part of the Brain Regulates Body Temperature?
• Why Do We Dream? (6 Theories and Psychological Reasons)

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10 Cool Chemistry Experiments

ThoughtCo / Hilary Allison

• Projects & Experiments
• Chemical Laws
• Periodic Table
• Scientific Method
• Biochemistry
• Physical Chemistry
• Medical Chemistry
• Chemistry In Everyday Life
• Famous Chemists
• Activities for Kids
• Abbreviations & Acronyms
• Weather & Climate
• Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
• B.A., Physics and Mathematics, Hastings College

Chemistry is king when it comes to making science cool. There are many interesting and fun projects to try, but these 10 chemistry experiments might be the coolest.

Whether you want to witness color transformations with copper and nitric acid or create a foam spectacle with hydrogen peroxide and potassium iodide, there's something here to spark curiosity in everyone. There's even a famous chemical reaction that will emit blue light and a characteristic barking or woofing sound.

Copper and Nitric Acid

When you place a piece of copper in nitric acid , the Cu 2+ ions and nitrate ions coordinate to color the solution green and then brownish-green. If you dilute the solution, water displaces nitrate ions around the copper, and the solution changes to blue.

Hydrogen Peroxide with Potassium Iodide

Affectionately known as elephant toothpaste , the chemical reaction between peroxide and potassium iodide shoots out a column of foam. If you add food coloring, you can customize the "toothpaste" for holiday-colored themes.

Any Alkali Metal in Water

Any of the alkali metals will react vigorously in water . How vigorously? Sodium burns bright yellow. Potassium burns violet. Lithium burns red. Cesium explodes. Experiment by moving down the alkali metals group of the periodic table. 

Thermite Reaction

The thermite reaction essentially shows what would happen if iron rusted instantly, rather than over time. In other words, it's making metal burn. If the conditions are right, just about any metal will burn. However, the reaction usually is performed by reacting iron oxide with aluminum:

Fe 2 O 3  + 2Al → 2Fe + Al 2 O 3  + heat and light

If you want a truly stunning display, try placing the mixture inside a block of dry ice and then lighting the mixture.

Coloring Fire

 SEAN GLADWELL / Getty Images

When ions are heated in a flame, electrons become excited and then drop to a lower energy state, emitting photons. The energy of the photons is characteristic of the chemical and corresponds to specific flame colors . It's the basis for the flame test in analytical chemistry , plus it's fun to experiment with different chemicals to see what colors they produce in a fire.

Make Polymer Bouncy Balls

Who doesn't enjoy playing with bouncy balls ? The chemical reaction used to make the balls makes a terrific experiment because you can alter the properties of the balls by changing the ratio of the ingredients.

Make a Lichtenberg Figure

A Lichtenberg figure or "electrical tree" is a record of the path taken by electrons during an electrostatic discharge. It's basically frozen lightning. There are several ways you can make an electrical tree.

Experiment with 'Hot Ice'

Hot ice is a name given to sodium acetate, a chemical you can make by reacting vinegar and baking soda. A solution of sodium acetate can be supercooled​ so that it will crystallize on command. Heat is evolved when the crystals form, so although it resembles water ice, it's hot.

Barking Dog Experiment

The Barking Dog is the name given to a chemiluminescent reaction involving the exothermic combination of either nitrous oxide or nitrogen monoxide with carbon disulfide. The reaction proceeds down a tube, emitting blue light and a characteristic "woof" sound.

Another version of the demonstration involves coating the inside of a clear jug with alcohol and igniting the vapor. The  flame front proceeds down the ​bottle , which also barks.

Dehydration of Sugar

When you react sugar with sulfuric acid , the sugar is violently dehydrated. The result is a growing column of carbon black, heat, and the overwhelming odor of burnt caramel.

Easy Science Experiments

Want something less extravagant but still fun? These easy science experiments are doable with items you likely already have at home—from creating invisible ink with baking soda to making homemade ice cream in a plastic bag.

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45 Cool Chemistry Experiments, Demos, and Science Fair Projects

Don’t forget your safety equipment!

Bunsen burners, colorful chemicals, and the possibility of a (controlled) explosion or two? Everybody loves chemistry experiments! We’ve rounded up the best activities, demos, and chemistry science fair projects for kids and teens. Try them in the classroom or at home.

Easy Chemistry Experiments and Activities for All Ages

Chemistry science fair projects.

These chemistry experiments and activities are all easy to do using simple supplies you probably already have. Families can try them at home, or teachers and students can do them together in the classroom.

Mix up some magic milk

Kids love this colorful experiment, which explores the concept of surface tension. This is one of our favorite chemistry experiments to try at home, since the supplies are so basic and the results are so cool!

Taste the Rainbow

Teach your students about diffusion while creating a beautiful and tasty rainbow. You’ll definitely want to have extra Skittles on hand so your class can enjoy a few as well!

Learn more: Skittles Diffusion

Crystallize sweet treats

Crystal science experiments teach kids about supersaturated solutions. This one is easy to do at home, and the results are absolutely delicious!

Learn more: Candy Crystals

Make elephant-sized toothpaste

This fun project uses yeast and a hydrogen peroxide solution to create overflowing “elephant toothpaste.” You can also add an extra fun layer by having kids create toothpaste wrappers for their plastic bottles.

Blow the biggest bubbles you can

Add a few simple ingredients to dish soap solution to create the largest bubbles you’ve ever seen! Kids learn about surface tension as they engineer these bubble-blowing wands.

Learn more: Giant Soap Bubbles

Demonstrate the “magic” leakproof bag

So simple and so amazing! All you need is a zip-top plastic bag, sharp pencils, and some water to blow your kids’ minds. Once they’re suitably impressed, teach them how the “trick” works by explaining the chemistry of polymers.

Learn more: Leakproof Bag

Use apple slices to learn about oxidation

Have students make predictions about what will happen to apple slices when immersed in different liquids, then put those predictions to the test! Finally, have them record their observations.

Learn more: Apple Oxidation

Float a marker man

Their eyes will pop out of their heads when you “levitate” a stick figure right off the table. This experiment works due to the insolubility of dry-erase marker ink in water, combined with the lighter density of the ink.

Learn more: Floating Marker Man

Discover density with hot and cold water

There are a lot of easy science experiments you can do with density. This one is extremely simple, involving only hot and cold water and food coloring, but the visuals make it appealing and fun.

Learn more: Layered Water

Layer more liquids

This density demo is a little more complicated, but the effects are spectacular. Slowly layer liquids like honey, dish soap, water, and rubbing alcohol in a glass. Kids will be amazed when the liquids float one on top of the other like magic (except it is really science).

Learn more: Layered Liquids

Grow a carbon sugar snake

Easy science experiments can still have impressive results. This eye-popping chemical reaction demonstration only requires simple supplies like sugar, baking soda, and sand.

Learn more: Carbon Sugar Snake

Make homemade bouncy balls

These homemade bouncy balls are easy to make since all you need is glue, food coloring, borax powder, cornstarch, and warm water. You’ll want to store them inside a container like a plastic egg because they will flatten out over time.

Learn more: Make Your Own Bouncy Balls

Create eggshell chalk

Eggshells contain calcium, the same material that makes chalk. Grind them up and mix them with flour, water, and food coloring to make your very own sidewalk chalk.

Learn more: Eggshell Chalk

Make naked eggs

This is so cool! Use vinegar to dissolve the calcium carbonate in an eggshell to discover the membrane underneath that holds the egg together. Then, use the “naked” egg for another easy science experiment that demonstrates osmosis .

Learn more: Naked Egg Experiment

Turn milk into plastic

This sounds a lot more complicated than it is, but don’t be afraid to give it a try. Use simple kitchen supplies to create plastic polymers from plain old milk. Sculpt them into cool shapes when you’re done.

Test pH using cabbage

Teach kids about acids and bases without needing pH test strips. Simply boil some red cabbage and use the resulting water to test various substances—acids turn red and bases turn green.

Learn more: Cabbage pH

Clean some old coins

Use common household items to make old oxidized coins clean and shiny again in this simple chemistry experiment. Ask kids to predict (hypothesize) which will work best, then expand the learning by doing some research to explain the results.

Learn more: Cleaning Coins

Blow up a balloon (without blowing)

Chances are good you probably did easy science experiments like this when you were in school yourself. This well-known activity demonstrates the reactions between acids and bases. Fill a bottle with vinegar and a balloon with baking soda. Fit the balloon over the top, shake the baking soda down into the vinegar, and watch the balloon inflate.

Learn more: Balloon Experiments

Assemble a DIY lava lamp

This 1970s trend is back—as an easy science experiment! This activity combines acid/base reactions with density for a totally groovy result.

Explore how sugary drinks affect teeth

The calcium content of eggshells makes them a great stand-in for teeth. Use eggs to explore how soda and juice can stain teeth and wear down the enamel. Expand your learning by trying different toothpaste and toothbrush combinations to see how effective they are.

Learn more: Sugar and Teeth Experiment

Mummify a hot dog

If your kids are fascinated by the Egyptians, they’ll love learning to mummify a hot dog. No need for canopic jars ; just grab some baking soda and get started.

Extinguish flames with carbon dioxide

This is a fiery twist on acid-base experiments. Light a candle and talk about what fire needs in order to survive. Then, create an acid-base reaction and “pour” the carbon dioxide to extinguish the flame. The CO2 gas acts like a liquid, suffocating the fire.

Send secret messages with invisible ink

Turn your kids into secret agents! Write messages with a paintbrush dipped in lemon juice, then hold the paper over a heat source and watch the invisible become visible as oxidation goes to work.

Learn more: Invisible Ink

Set popcorn dancing

This is a fun version of the classic baking soda and vinegar experiment, perfect for the younger crowd. The bubbly mixture causes popcorn to dance around in the water.

Learn more: Dancing Popcorn Experiment

Shoot a soda geyser sky-high

You’ve always wondered if this really works, so it’s time to find out for yourself! Kids will marvel at the chemical reaction that sends diet soda shooting high in the air when Mentos are added.

Learn more: Mentos and Coke Experiment

All of these chemistry experiments are perfect for using the scientific method. Form a hypothesis, alter the variables, and then observe the results! You can simplify these projects for younger kids, or add more complexity for older students.

Break apart covalent bonds

Difficulty: Medium / Materials: Medium

Break the covalent bond of H 2 O into H and O with this simple experiment. You only need simple supplies for this one. Turn it into a science fair project by changing up the variables—does the temperature of the water matter? What happens if you try this with other liquids?

Learn more: Breaking Covalent Bonds

Measure the calories in various foods

Are the calorie counts on your favorite snacks accurate? Build your own calorimeter and find out! This kit from Home Science Tools has all the supplies you’ll need.

Detect latent fingerprints

Forensic science is engrossing and can lead to important career opportunities too. Explore the chemistry needed to detect latent (invisible) fingerprints, just like they do for crime scenes!

Learn more: Fingerprints Project

Use Alka-Seltzer to explore reaction rate

Difficulty: Easy / Materials: Easy

Tweak this basic concept to create a variety of high school chemistry science fair projects. Change the temperature, surface area, pressure, and more to see how reaction rates change.

Determine whether sports drinks really have more electrolytes than other beverages

Difficulty: Medium / Materials: Advanced

Are those pricey sports drinks really worth it? Try this experiment to find out. You’ll need some special equipment for this one; buy a complete kit at Home Science Tools .

Turn flames into a rainbow

You’ll need to get your hands on a few different chemicals for this experiment, but the wow factor will make it worth the effort. Make it a science project by seeing if different materials, air temperature, or other factors change the results.

Discover the size of a mole

The mole is a key concept in chemistry, so it’s important to ensure students really understand it. This experiment uses simple materials like salt and chalk to make an abstract concept more concrete. Make it a project by applying the same procedure to a variety of substances, or determining whether outside variables have an effect on the results.

Learn more: How Big Is a Mole?

Cook up candy to learn mole and molecule calculations

This edible experiment lets students make their own peppermint hard candy while they calculate mass, moles, molecules, and formula weights. Tweak the formulas to create different types of candy and make this into a sweet science fair project!

Learn more: Candy Chemistry

Make soap to understand saponification

Take a closer look at an everyday item: soap! Use oils and other ingredients to make your own soap, learning about esters and saponification. Tinker with the formula to find one that fits a particular set of parameters.

Learn more: Saponification

Uncover the secrets of evaporation

Explore the factors that affect evaporation, then come up with ways to slow them down or speed them up for a simple science fair project.

Learn more: Evaporation

More Chemistry Experiment Science Fair Ideas

These questions and prompts can spark ideas for unique chemistry experiments:

• Compare the properties of sugar and artificial sweeteners.
• Explore the impact of temperature, concentration, and seeding on crystal growth.
• Test various antacids on the market to find the most effective product.
• What is the optimum temperature for yeast production when baking bread from scratch?
• Compare the vitamin C content of various fruits and vegetables.
• How does temperature affect enzyme-catalyzed reactions?
• Investigate the effects of pH on an acid-base chemical reaction.
• Devise a new natural way to test pH levels (such as cabbage leaves).
• What’s the best way to slow down metal oxidation (the form of rust)?
• How do changes in ingredients and method affect the results of a baking recipe?

Like these chemistry experiments? Don’t miss STEM Activities for Kids of All Ages and Interests .

Plus, get all the latest teaching news and ideas when you sign up for our free newsletters.

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Hands on kids activities for hands on moms. Focusing on kids activities perfect for toddlers and preschoolers.

50 Amazingly Simple Science Experiments for Kids at Home

Science Kindergartners Preschoolers Experiment Resources 30 Comments

Kids love experimenting , and these 50 simple science experiments for kids at home from Brigitte are perfect for all ages! Plus, you probably already have the basic supplies at home.

My daughters and I have had a lot of fun doing science experiments. Each year when we create our spring and summer list , we make sure to include “science days” which are days filled with science experiments.

Sometimes our science experiments don’t work according to plan, but I have been told that all scientists have failures with experiments from time to time.

It’s okay if they aren’t all successes.

Get the FREE Science Experiments Download

50 Simple Science Experiments with Supplies You Already Have

I love these 50 simple science experiments for you to try with your little scientists. They all use basic household supplies that you probably already have at home!

Most of these are experiments my daughters and I have done together. I hope you enjoy them as much as we have!

Get little ones involved with these easy toddler-friendly science experiment ideas!

Simple Science Experiments with Water

Not only can water  be a blast to play in, but water plus a few basic supplies equals a lot of science fun!

• Make an orange sink and float with an orange buoyancy experiment from Playdough to Plato.
• Compare the amount of salt in different types of water with this salty egg experiment  as seen on Uplifting Mayhem.
• Do a little more sinking or floating with a fun sink or float experiment  even toddlers can do from Hands On As We Grow.
• Use the free printable to record what sinks or floats in an outdoor experiment from Buggy and Buddy.
• Create some beautiful pieces of paper with this rainbow paper experiment from Science Kiddo.
• Talk about solutions as you try the “what dissolves in water” experiment  as seen on Hands On As We Grow.
• Learn about water absorption with this simple experiment from Little Bins for Little Hands.
• Mix some fun colors with this oil and water experiment  from Fun Learning for Kids.
• Make your own lava lamp , just like on  Hands On As We Grow.
• Can you keep all the water in the bag? Try it with a  leak-proof bag experiment  as seen on Hands On As We Grow.
• Learn about surface tension with this  magic finger pepper experiment  found on Hands On As We Grow.
• Make your own  water cycle in a bottle  as seen on A Dab of Glue Will Do.

Simple Science Experiments with Baking Soda and Vinegar

Baking soda + vinegar = a great chemical reaction! This fizzy reaction can fuel a variety of simple science experiments at home.

First of all, we have tested and found out the absolute best combination of baking soda and vinegar to get the best reaction possible. It makes a difference if you add vinegar to baking soda or vice versa! And how much you use!

• Inflate a balloon without blowing into it with a baking soda and vinegar balloon experiment  as seen on Little Bins for Little Hands.
• Practice colors as you do a baking soda and vinegar with color experiment as seen on Hands On As We Grow.
• Have fun outside with an outdoor volcano eruption  as seen on Preschool Inspirations.
• Have more volcano fun by making apple volcanoes as seen on The Resourceful Mama.
• Learn about acids and bases and the chemical reaction that occurs when you make apple seeds dance with a   jumping apple seeds experiment  as seen on JDaniel4s Mom.
• Watch some rice dance with a   dancing rice experiment as seen on Green Kid Crafts.
• Continue your dance party by making raisins dance with a dancing raisin experiment  as seen on 123 Homeschool 4 Me. What other items can you get to dance?
• Learn more about acids and bases by dissolving a sea shell as seen on Teach Beside Me.
• Make an egg shell disappear with this disappearing egg activity  as seen on Premeditated Leftovers.
• See how far you can launch a soda bottle with this baking soda powered boat as seen on Science Sparks.
• Make your own rocks (or eggs) with this fizzy treasure rocks experiment as seen on Living Life and Learning.
• Have some fun this summer with this frozen vinegar experiment as seen on Inspiration Laboratories.

Plant Themed Simple Science Experiments

Enjoy learning about seeds, plant parts, and how plants grow with these simple science experiments.

• Learn about how plants soak up water through their stems with a flower experiment for kids  from Growing A Jeweled Rose.
• Watch seeds sprout as you grow seeds in a jar  as seen on Teaching Mama.
• Learn about the parts of the seed with a seed coat experiment as seen on Gift of Curiosity.
• Build a house out of sponges and then watch it sprout with this sprout house as seen on The Stem Laboratory.
• Learn what liquids allow seeds to grow the best with this seed experiment  as seen on Gift of Curiosity.
• Explore how plants grow towards the light with this shoe-box maze experiment from Plants for Kids.

Animal Themed Simple Science Experiments

Learning about animals can be even more fun with some simple hands-on simple science experiments.

• Find out more about giraffes and create some giraffe spots  as seen on Preschool Powol Packets.
• Learn about how animals in the Arctic keep warm by making an arctic glove  as seen on Steve Spangler Science.
• Discover how penguins stay dry with a penguin feather experiment as seen on Raising Little Superheroes.
• Learn about different bird beaks with a bird beak experiment as seen on Blessed Beyond a Doubt.
• Explore how fish (and hermit crabs) breathe with this gill experiment  as seen on Preschool Powol Packets.
• Learn about sharks with a   shark buoyancy experiment as seen on Little Bins for Little Hands.

Even More Simple Science Experiment for Kids at Home!

If you are still looking for more science fun, you may enjoy the following simple science experiments.

• Find out how sugary drinks hurt teeth with an  eggs-periment  as seen on Feels Like Home Blog.
• Discover geodes (the state rock of Iowa) with this eggshell geode crystal experiment  as seen on Science Bob.
• Learn about air pressure with an egg and bottle experiment  as seen on Science Sparks.
• Find out what causes an apple to brown with this apple science experiment  as seen on Teach Beside Me.
• Make an  edible bubble apple with an experiment as seen on Preschool Powol Packet.
• Learn more about surface tension with a penny and water experiment  as seen on Artful Parent.
• Mix colors like magic with this color changing milk experiment  from Hands On As We Grow.
• Blow up a balloon with this soda and balloon experiment from Learn Play Imagine.
• Practice letters by making beautiful crystal letters as seen on Books and Giggles.
• Make your own indoor hovercraft  as seen on Living Life and Learning.
• Learn about colors with this beautiful butterfly chromatography craft  as seen on Buggy and Buddy.
• Make soap souffle  as seen on Steve Spangler Science.
• After talking about liquids and solids (and finding them in your own home), create oobleck  as seen on Babble Dabble Do. Is it a liquid, or is it a solid?
• Learn about frost by making some indoor frost as seen on Little Bin for Little Hands.
• Make your own homemade butter in a jar as seen on Happy Hooligans.

What scientific experiment will you try first?

About Brigitte Brulz

Brigitte Brulz is a homeschooling mom of two daughters, wife of her high school sweetheart, and author of Jobs of a Preschooler and Pickles, Pickles, I Like Pickles. She offers free coloring pages and activity ideas on her website at BrigitteBrulz.com .

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Reader Interactions

30 comments.

college brawl says

March 13, 2024 at 1:05 am

Wow, these experiments look like so much fun! I can’t wait to try them out with my kids. We’re always looking for new and creative ways to learn about science at home, and these experiments look like they’ll be perfect for us. Thanks for sharing! 😊

threadsBay says

August 31, 2023 at 3:13 am

I love science experiments! This one is really simple and easy to do.

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• A Quick Guide to Experimental Design | 5 Steps & Examples

A Quick Guide to Experimental Design | 5 Steps & Examples

Published on 11 April 2022 by Rebecca Bevans . Revised on 5 December 2022.

Experiments are used to study causal relationships . You manipulate one or more independent variables and measure their effect on one or more dependent variables.

Experimental design means creating a set of procedures to systematically test a hypothesis . A good experimental design requires a strong understanding of the system you are studying. 

There are five key steps in designing an experiment:

• Consider your variables and how they are related
• Write a specific, testable hypothesis
• Design experimental treatments to manipulate your independent variable
• Assign subjects to groups, either between-subjects or within-subjects
• Plan how you will measure your dependent variable

For valid conclusions, you also need to select a representative sample and control any  extraneous variables that might influence your results. If if random assignment of participants to control and treatment groups is impossible, unethical, or highly difficult, consider an observational study instead.

Table of contents

Step 1: define your variables, step 2: write your hypothesis, step 3: design your experimental treatments, step 4: assign your subjects to treatment groups, step 5: measure your dependent variable, frequently asked questions about experimental design.

You should begin with a specific research question . We will work with two research question examples, one from health sciences and one from ecology:

To translate your research question into an experimental hypothesis, you need to define the main variables and make predictions about how they are related.

Start by simply listing the independent and dependent variables .

Then you need to think about possible extraneous and confounding variables and consider how you might control  them in your experiment.

Finally, you can put these variables together into a diagram. Use arrows to show the possible relationships between variables and include signs to show the expected direction of the relationships.

Here we predict that increasing temperature will increase soil respiration and decrease soil moisture, while decreasing soil moisture will lead to decreased soil respiration.

Prevent plagiarism, run a free check.

Now that you have a strong conceptual understanding of the system you are studying, you should be able to write a specific, testable hypothesis that addresses your research question.

The next steps will describe how to design a controlled experiment . In a controlled experiment, you must be able to:

• Systematically and precisely manipulate the independent variable(s).
• Precisely measure the dependent variable(s).
• Control any potential confounding variables.

If your study system doesn’t match these criteria, there are other types of research you can use to answer your research question.

How you manipulate the independent variable can affect the experiment’s external validity – that is, the extent to which the results can be generalised and applied to the broader world.

First, you may need to decide how widely to vary your independent variable.

• just slightly above the natural range for your study region.
• over a wider range of temperatures to mimic future warming.
• over an extreme range that is beyond any possible natural variation.

Second, you may need to choose how finely to vary your independent variable. Sometimes this choice is made for you by your experimental system, but often you will need to decide, and this will affect how much you can infer from your results.

• a categorical variable : either as binary (yes/no) or as levels of a factor (no phone use, low phone use, high phone use).
• a continuous variable (minutes of phone use measured every night).

How you apply your experimental treatments to your test subjects is crucial for obtaining valid and reliable results.

First, you need to consider the study size : how many individuals will be included in the experiment? In general, the more subjects you include, the greater your experiment’s statistical power , which determines how much confidence you can have in your results.

Then you need to randomly assign your subjects to treatment groups . Each group receives a different level of the treatment (e.g. no phone use, low phone use, high phone use).

You should also include a control group , which receives no treatment. The control group tells us what would have happened to your test subjects without any experimental intervention.

When assigning your subjects to groups, there are two main choices you need to make:

• A completely randomised design vs a randomised block design .
• A between-subjects design vs a within-subjects design .

Randomisation

An experiment can be completely randomised or randomised within blocks (aka strata):

• In a completely randomised design , every subject is assigned to a treatment group at random.
• In a randomised block design (aka stratified random design), subjects are first grouped according to a characteristic they share, and then randomly assigned to treatments within those groups.

Sometimes randomisation isn’t practical or ethical , so researchers create partially-random or even non-random designs. An experimental design where treatments aren’t randomly assigned is called a quasi-experimental design .

Between-subjects vs within-subjects

In a between-subjects design (also known as an independent measures design or classic ANOVA design), individuals receive only one of the possible levels of an experimental treatment.

In medical or social research, you might also use matched pairs within your between-subjects design to make sure that each treatment group contains the same variety of test subjects in the same proportions.

In a within-subjects design (also known as a repeated measures design), every individual receives each of the experimental treatments consecutively, and their responses to each treatment are measured.

Within-subjects or repeated measures can also refer to an experimental design where an effect emerges over time, and individual responses are measured over time in order to measure this effect as it emerges.

Counterbalancing (randomising or reversing the order of treatments among subjects) is often used in within-subjects designs to ensure that the order of treatment application doesn’t influence the results of the experiment.

Finally, you need to decide how you’ll collect data on your dependent variable outcomes. You should aim for reliable and valid measurements that minimise bias or error.

Some variables, like temperature, can be objectively measured with scientific instruments. Others may need to be operationalised to turn them into measurable observations.

• Ask participants to record what time they go to sleep and get up each day.
• Ask participants to wear a sleep tracker.

How precisely you measure your dependent variable also affects the kinds of statistical analysis you can use on your data.

Experiments are always context-dependent, and a good experimental design will take into account all of the unique considerations of your study system to produce information that is both valid and relevant to your research question.

Experimental designs are a set of procedures that you plan in order to examine the relationship between variables that interest you.

To design a successful experiment, first identify:

• A testable hypothesis
• One or more independent variables that you will manipulate
• One or more dependent variables that you will measure

When designing the experiment, first decide:

• How your variable(s) will be manipulated
• How you will control for any potential confounding or lurking variables
• How many subjects you will include
• How you will assign treatments to your subjects

The key difference between observational studies and experiments is that, done correctly, an observational study will never influence the responses or behaviours of participants. Experimental designs will have a treatment condition applied to at least a portion of participants.

A confounding variable , also called a confounder or confounding factor, is a third variable in a study examining a potential cause-and-effect relationship.

A confounding variable is related to both the supposed cause and the supposed effect of the study. It can be difficult to separate the true effect of the independent variable from the effect of the confounding variable.

In your research design , it’s important to identify potential confounding variables and plan how you will reduce their impact.

In a between-subjects design , every participant experiences only one condition, and researchers assess group differences between participants in various conditions.

In a within-subjects design , each participant experiences all conditions, and researchers test the same participants repeatedly for differences between conditions.

The word ‘between’ means that you’re comparing different conditions between groups, while the word ‘within’ means you’re comparing different conditions within the same group.

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Bevans, R. (2022, December 05). A Quick Guide to Experimental Design | 5 Steps & Examples. Scribbr. Retrieved 27 September 2024, from https://www.scribbr.co.uk/research-methods/guide-to-experimental-design/

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Okay, this is the hardest part of the whole project…picking your topic. But here are some ideas to get you started. Even if you don’t like any, they may inspire you to come up with one of your own. Remember, check all project ideas with your teacher and parents, and don’t do any project that would hurt or scare people or animals. Good luck!

• Does music affect on animal behavior?
• Does the color of food or drinks affect whether or not we like them?
• Where are the most germs in your school? ( CLICK for more info. )
• Does music have an affect on plant growth?
• Which kind of food do dogs (or any animal) prefer best?
• Which paper towel brand is the strongest?
• What is the best way to keep an ice cube from melting?
• What level of salt works best to hatch brine shrimp?
• Can the food we eat affect our heart rate?
• How effective are child-proof containers and locks.
• Can background noise levels affect how well we concentrate?
• Does acid rain affect the growth of aquatic plants?
• What is the best way to keep cut flowers fresh the longest?
• Does the color of light used on plants affect how well they grow?
• What plant fertilizer works best?
• Does the color of a room affect human behavior?
• Do athletic students have better lung capacity?
• What brand of battery lasts the longest?
• Does the type of potting soil used in planting affect how fast the plant grows?
• What type of food allow mold to grow the fastest?
• Does having worms in soil help plants grow faster?
• Can plants grow in pots if they are sideways or upside down?
• Does the color of hair affect how much static electricity it can carry? (test with balloons)
• How much weight can the surface tension of water hold?
• Can some people really read someone else’s thoughts?
• Which soda decays fallen out teeth the most?
• What light brightness makes plants grow the best?
• Does the color of birdseed affect how much birds will eat it?
• Do natural or chemical fertilizers work best?
• Can mice learn? (you can pick any animal)
• Can people tell artificial smells from real ones?
• What brands of bubble gum produce the biggest bubbles?
• Does age affect human reaction times?
• What is the effect of salt on the boiling temperature of water?
• Does shoe design really affect an athlete’s jumping height?
• What type of grass seed grows the fastest?
• Can animals see in the dark better than humans?

Didn’t see one you like? Don’t worry…look over them again and see if they give you an idea for your own project that will work for you. Remember, find something that interests you, and have fun with it.

To download and print this list of ideas CLICK HERE .

• The scientific method
• science fair resources
• a little helpful advice

6.2 Experimental Design

Learning objectives.

• Explain the difference between between-subjects and within-subjects experiments, list some of the pros and cons of each approach, and decide which approach to use to answer a particular research question.
• Define random assignment, distinguish it from random sampling, explain its purpose in experimental research, and use some simple strategies to implement it.
• Define what a control condition is, explain its purpose in research on treatment effectiveness, and describe some alternative types of control conditions.
• Define several types of carryover effect, give examples of each, and explain how counterbalancing helps to deal with them.

In this section, we look at some different ways to design an experiment. The primary distinction we will make is between approaches in which each participant experiences one level of the independent variable and approaches in which each participant experiences all levels of the independent variable. The former are called between-subjects experiments and the latter are called within-subjects experiments.

Between-Subjects Experiments

In a between-subjects experiment , each participant is tested in only one condition. For example, a researcher with a sample of 100 college students might assign half of them to write about a traumatic event and the other half write about a neutral event. Or a researcher with a sample of 60 people with severe agoraphobia (fear of open spaces) might assign 20 of them to receive each of three different treatments for that disorder. It is essential in a between-subjects experiment that the researcher assign participants to conditions so that the different groups are, on average, highly similar to each other. Those in a trauma condition and a neutral condition, for example, should include a similar proportion of men and women, and they should have similar average intelligence quotients (IQs), similar average levels of motivation, similar average numbers of health problems, and so on. This is a matter of controlling these extraneous participant variables across conditions so that they do not become confounding variables.

Random Assignment

The primary way that researchers accomplish this kind of control of extraneous variables across conditions is called random assignment , which means using a random process to decide which participants are tested in which conditions. Do not confuse random assignment with random sampling. Random sampling is a method for selecting a sample from a population, and it is rarely used in psychological research. Random assignment is a method for assigning participants in a sample to the different conditions, and it is an important element of all experimental research in psychology and other fields too.

In its strictest sense, random assignment should meet two criteria. One is that each participant has an equal chance of being assigned to each condition (e.g., a 50% chance of being assigned to each of two conditions). The second is that each participant is assigned to a condition independently of other participants. Thus one way to assign participants to two conditions would be to flip a coin for each one. If the coin lands heads, the participant is assigned to Condition A, and if it lands tails, the participant is assigned to Condition B. For three conditions, one could use a computer to generate a random integer from 1 to 3 for each participant. If the integer is 1, the participant is assigned to Condition A; if it is 2, the participant is assigned to Condition B; and if it is 3, the participant is assigned to Condition C. In practice, a full sequence of conditions—one for each participant expected to be in the experiment—is usually created ahead of time, and each new participant is assigned to the next condition in the sequence as he or she is tested. When the procedure is computerized, the computer program often handles the random assignment.

One problem with coin flipping and other strict procedures for random assignment is that they are likely to result in unequal sample sizes in the different conditions. Unequal sample sizes are generally not a serious problem, and you should never throw away data you have already collected to achieve equal sample sizes. However, for a fixed number of participants, it is statistically most efficient to divide them into equal-sized groups. It is standard practice, therefore, to use a kind of modified random assignment that keeps the number of participants in each group as similar as possible. One approach is block randomization . In block randomization, all the conditions occur once in the sequence before any of them is repeated. Then they all occur again before any of them is repeated again. Within each of these “blocks,” the conditions occur in a random order. Again, the sequence of conditions is usually generated before any participants are tested, and each new participant is assigned to the next condition in the sequence. Table 6.2 “Block Randomization Sequence for Assigning Nine Participants to Three Conditions” shows such a sequence for assigning nine participants to three conditions. The Research Randomizer website ( http://www.randomizer.org ) will generate block randomization sequences for any number of participants and conditions. Again, when the procedure is computerized, the computer program often handles the block randomization.

Table 6.2 Block Randomization Sequence for Assigning Nine Participants to Three Conditions

Random assignment is not guaranteed to control all extraneous variables across conditions. It is always possible that just by chance, the participants in one condition might turn out to be substantially older, less tired, more motivated, or less depressed on average than the participants in another condition. However, there are some reasons that this is not a major concern. One is that random assignment works better than one might expect, especially for large samples. Another is that the inferential statistics that researchers use to decide whether a difference between groups reflects a difference in the population takes the “fallibility” of random assignment into account. Yet another reason is that even if random assignment does result in a confounding variable and therefore produces misleading results, this is likely to be detected when the experiment is replicated. The upshot is that random assignment to conditions—although not infallible in terms of controlling extraneous variables—is always considered a strength of a research design.

Treatment and Control Conditions

Between-subjects experiments are often used to determine whether a treatment works. In psychological research, a treatment is any intervention meant to change people’s behavior for the better. This includes psychotherapies and medical treatments for psychological disorders but also interventions designed to improve learning, promote conservation, reduce prejudice, and so on. To determine whether a treatment works, participants are randomly assigned to either a treatment condition , in which they receive the treatment, or a control condition , in which they do not receive the treatment. If participants in the treatment condition end up better off than participants in the control condition—for example, they are less depressed, learn faster, conserve more, express less prejudice—then the researcher can conclude that the treatment works. In research on the effectiveness of psychotherapies and medical treatments, this type of experiment is often called a randomized clinical trial .

There are different types of control conditions. In a no-treatment control condition , participants receive no treatment whatsoever. One problem with this approach, however, is the existence of placebo effects. A placebo is a simulated treatment that lacks any active ingredient or element that should make it effective, and a placebo effect is a positive effect of such a treatment. Many folk remedies that seem to work—such as eating chicken soup for a cold or placing soap under the bedsheets to stop nighttime leg cramps—are probably nothing more than placebos. Although placebo effects are not well understood, they are probably driven primarily by people’s expectations that they will improve. Having the expectation to improve can result in reduced stress, anxiety, and depression, which can alter perceptions and even improve immune system functioning (Price, Finniss, & Benedetti, 2008).

Placebo effects are interesting in their own right (see Note 6.28 “The Powerful Placebo” ), but they also pose a serious problem for researchers who want to determine whether a treatment works. Figure 6.2 “Hypothetical Results From a Study Including Treatment, No-Treatment, and Placebo Conditions” shows some hypothetical results in which participants in a treatment condition improved more on average than participants in a no-treatment control condition. If these conditions (the two leftmost bars in Figure 6.2 “Hypothetical Results From a Study Including Treatment, No-Treatment, and Placebo Conditions” ) were the only conditions in this experiment, however, one could not conclude that the treatment worked. It could be instead that participants in the treatment group improved more because they expected to improve, while those in the no-treatment control condition did not.

Figure 6.2 Hypothetical Results From a Study Including Treatment, No-Treatment, and Placebo Conditions

Fortunately, there are several solutions to this problem. One is to include a placebo control condition , in which participants receive a placebo that looks much like the treatment but lacks the active ingredient or element thought to be responsible for the treatment’s effectiveness. When participants in a treatment condition take a pill, for example, then those in a placebo control condition would take an identical-looking pill that lacks the active ingredient in the treatment (a “sugar pill”). In research on psychotherapy effectiveness, the placebo might involve going to a psychotherapist and talking in an unstructured way about one’s problems. The idea is that if participants in both the treatment and the placebo control groups expect to improve, then any improvement in the treatment group over and above that in the placebo control group must have been caused by the treatment and not by participants’ expectations. This is what is shown by a comparison of the two outer bars in Figure 6.2 “Hypothetical Results From a Study Including Treatment, No-Treatment, and Placebo Conditions” .

Of course, the principle of informed consent requires that participants be told that they will be assigned to either a treatment or a placebo control condition—even though they cannot be told which until the experiment ends. In many cases the participants who had been in the control condition are then offered an opportunity to have the real treatment. An alternative approach is to use a waitlist control condition , in which participants are told that they will receive the treatment but must wait until the participants in the treatment condition have already received it. This allows researchers to compare participants who have received the treatment with participants who are not currently receiving it but who still expect to improve (eventually). A final solution to the problem of placebo effects is to leave out the control condition completely and compare any new treatment with the best available alternative treatment. For example, a new treatment for simple phobia could be compared with standard exposure therapy. Because participants in both conditions receive a treatment, their expectations about improvement should be similar. This approach also makes sense because once there is an effective treatment, the interesting question about a new treatment is not simply “Does it work?” but “Does it work better than what is already available?”

The Powerful Placebo

Many people are not surprised that placebos can have a positive effect on disorders that seem fundamentally psychological, including depression, anxiety, and insomnia. However, placebos can also have a positive effect on disorders that most people think of as fundamentally physiological. These include asthma, ulcers, and warts (Shapiro & Shapiro, 1999). There is even evidence that placebo surgery—also called “sham surgery”—can be as effective as actual surgery.

Medical researcher J. Bruce Moseley and his colleagues conducted a study on the effectiveness of two arthroscopic surgery procedures for osteoarthritis of the knee (Moseley et al., 2002). The control participants in this study were prepped for surgery, received a tranquilizer, and even received three small incisions in their knees. But they did not receive the actual arthroscopic surgical procedure. The surprising result was that all participants improved in terms of both knee pain and function, and the sham surgery group improved just as much as the treatment groups. According to the researchers, “This study provides strong evidence that arthroscopic lavage with or without débridement [the surgical procedures used] is not better than and appears to be equivalent to a placebo procedure in improving knee pain and self-reported function” (p. 85).

Research has shown that patients with osteoarthritis of the knee who receive a “sham surgery” experience reductions in pain and improvement in knee function similar to those of patients who receive a real surgery.

Army Medicine – Surgery – CC BY 2.0.

Within-Subjects Experiments

In a within-subjects experiment , each participant is tested under all conditions. Consider an experiment on the effect of a defendant’s physical attractiveness on judgments of his guilt. Again, in a between-subjects experiment, one group of participants would be shown an attractive defendant and asked to judge his guilt, and another group of participants would be shown an unattractive defendant and asked to judge his guilt. In a within-subjects experiment, however, the same group of participants would judge the guilt of both an attractive and an unattractive defendant.

The primary advantage of this approach is that it provides maximum control of extraneous participant variables. Participants in all conditions have the same mean IQ, same socioeconomic status, same number of siblings, and so on—because they are the very same people. Within-subjects experiments also make it possible to use statistical procedures that remove the effect of these extraneous participant variables on the dependent variable and therefore make the data less “noisy” and the effect of the independent variable easier to detect. We will look more closely at this idea later in the book.

Carryover Effects and Counterbalancing

The primary disadvantage of within-subjects designs is that they can result in carryover effects. A carryover effect is an effect of being tested in one condition on participants’ behavior in later conditions. One type of carryover effect is a practice effect , where participants perform a task better in later conditions because they have had a chance to practice it. Another type is a fatigue effect , where participants perform a task worse in later conditions because they become tired or bored. Being tested in one condition can also change how participants perceive stimuli or interpret their task in later conditions. This is called a context effect . For example, an average-looking defendant might be judged more harshly when participants have just judged an attractive defendant than when they have just judged an unattractive defendant. Within-subjects experiments also make it easier for participants to guess the hypothesis. For example, a participant who is asked to judge the guilt of an attractive defendant and then is asked to judge the guilt of an unattractive defendant is likely to guess that the hypothesis is that defendant attractiveness affects judgments of guilt. This could lead the participant to judge the unattractive defendant more harshly because he thinks this is what he is expected to do. Or it could make participants judge the two defendants similarly in an effort to be “fair.”

Carryover effects can be interesting in their own right. (Does the attractiveness of one person depend on the attractiveness of other people that we have seen recently?) But when they are not the focus of the research, carryover effects can be problematic. Imagine, for example, that participants judge the guilt of an attractive defendant and then judge the guilt of an unattractive defendant. If they judge the unattractive defendant more harshly, this might be because of his unattractiveness. But it could be instead that they judge him more harshly because they are becoming bored or tired. In other words, the order of the conditions is a confounding variable. The attractive condition is always the first condition and the unattractive condition the second. Thus any difference between the conditions in terms of the dependent variable could be caused by the order of the conditions and not the independent variable itself.

There is a solution to the problem of order effects, however, that can be used in many situations. It is counterbalancing , which means testing different participants in different orders. For example, some participants would be tested in the attractive defendant condition followed by the unattractive defendant condition, and others would be tested in the unattractive condition followed by the attractive condition. With three conditions, there would be six different orders (ABC, ACB, BAC, BCA, CAB, and CBA), so some participants would be tested in each of the six orders. With counterbalancing, participants are assigned to orders randomly, using the techniques we have already discussed. Thus random assignment plays an important role in within-subjects designs just as in between-subjects designs. Here, instead of randomly assigning to conditions, they are randomly assigned to different orders of conditions. In fact, it can safely be said that if a study does not involve random assignment in one form or another, it is not an experiment.

There are two ways to think about what counterbalancing accomplishes. One is that it controls the order of conditions so that it is no longer a confounding variable. Instead of the attractive condition always being first and the unattractive condition always being second, the attractive condition comes first for some participants and second for others. Likewise, the unattractive condition comes first for some participants and second for others. Thus any overall difference in the dependent variable between the two conditions cannot have been caused by the order of conditions. A second way to think about what counterbalancing accomplishes is that if there are carryover effects, it makes it possible to detect them. One can analyze the data separately for each order to see whether it had an effect.

When 9 Is “Larger” Than 221

Researcher Michael Birnbaum has argued that the lack of context provided by between-subjects designs is often a bigger problem than the context effects created by within-subjects designs. To demonstrate this, he asked one group of participants to rate how large the number 9 was on a 1-to-10 rating scale and another group to rate how large the number 221 was on the same 1-to-10 rating scale (Birnbaum, 1999). Participants in this between-subjects design gave the number 9 a mean rating of 5.13 and the number 221 a mean rating of 3.10. In other words, they rated 9 as larger than 221! According to Birnbaum, this is because participants spontaneously compared 9 with other one-digit numbers (in which case it is relatively large) and compared 221 with other three-digit numbers (in which case it is relatively small).

Simultaneous Within-Subjects Designs

So far, we have discussed an approach to within-subjects designs in which participants are tested in one condition at a time. There is another approach, however, that is often used when participants make multiple responses in each condition. Imagine, for example, that participants judge the guilt of 10 attractive defendants and 10 unattractive defendants. Instead of having people make judgments about all 10 defendants of one type followed by all 10 defendants of the other type, the researcher could present all 20 defendants in a sequence that mixed the two types. The researcher could then compute each participant’s mean rating for each type of defendant. Or imagine an experiment designed to see whether people with social anxiety disorder remember negative adjectives (e.g., “stupid,” “incompetent”) better than positive ones (e.g., “happy,” “productive”). The researcher could have participants study a single list that includes both kinds of words and then have them try to recall as many words as possible. The researcher could then count the number of each type of word that was recalled. There are many ways to determine the order in which the stimuli are presented, but one common way is to generate a different random order for each participant.

Between-Subjects or Within-Subjects?

Almost every experiment can be conducted using either a between-subjects design or a within-subjects design. This means that researchers must choose between the two approaches based on their relative merits for the particular situation.

Between-subjects experiments have the advantage of being conceptually simpler and requiring less testing time per participant. They also avoid carryover effects without the need for counterbalancing. Within-subjects experiments have the advantage of controlling extraneous participant variables, which generally reduces noise in the data and makes it easier to detect a relationship between the independent and dependent variables.

A good rule of thumb, then, is that if it is possible to conduct a within-subjects experiment (with proper counterbalancing) in the time that is available per participant—and you have no serious concerns about carryover effects—this is probably the best option. If a within-subjects design would be difficult or impossible to carry out, then you should consider a between-subjects design instead. For example, if you were testing participants in a doctor’s waiting room or shoppers in line at a grocery store, you might not have enough time to test each participant in all conditions and therefore would opt for a between-subjects design. Or imagine you were trying to reduce people’s level of prejudice by having them interact with someone of another race. A within-subjects design with counterbalancing would require testing some participants in the treatment condition first and then in a control condition. But if the treatment works and reduces people’s level of prejudice, then they would no longer be suitable for testing in the control condition. This is true for many designs that involve a treatment meant to produce long-term change in participants’ behavior (e.g., studies testing the effectiveness of psychotherapy). Clearly, a between-subjects design would be necessary here.

Remember also that using one type of design does not preclude using the other type in a different study. There is no reason that a researcher could not use both a between-subjects design and a within-subjects design to answer the same research question. In fact, professional researchers often do exactly this.

Key Takeaways

• Experiments can be conducted using either between-subjects or within-subjects designs. Deciding which to use in a particular situation requires careful consideration of the pros and cons of each approach.
• Random assignment to conditions in between-subjects experiments or to orders of conditions in within-subjects experiments is a fundamental element of experimental research. Its purpose is to control extraneous variables so that they do not become confounding variables.
• Experimental research on the effectiveness of a treatment requires both a treatment condition and a control condition, which can be a no-treatment control condition, a placebo control condition, or a waitlist control condition. Experimental treatments can also be compared with the best available alternative.

Discussion: For each of the following topics, list the pros and cons of a between-subjects and within-subjects design and decide which would be better.

• You want to test the relative effectiveness of two training programs for running a marathon.
• Using photographs of people as stimuli, you want to see if smiling people are perceived as more intelligent than people who are not smiling.
• In a field experiment, you want to see if the way a panhandler is dressed (neatly vs. sloppily) affects whether or not passersby give him any money.
• You want to see if concrete nouns (e.g., dog ) are recalled better than abstract nouns (e.g., truth ).
• Discussion: Imagine that an experiment shows that participants who receive psychodynamic therapy for a dog phobia improve more than participants in a no-treatment control group. Explain a fundamental problem with this research design and at least two ways that it might be corrected.

Birnbaum, M. H. (1999). How to show that 9 > 221: Collect judgments in a between-subjects design. Psychological Methods, 4 , 243–249.

Moseley, J. B., O’Malley, K., Petersen, N. J., Menke, T. J., Brody, B. A., Kuykendall, D. H., … Wray, N. P. (2002). A controlled trial of arthroscopic surgery for osteoarthritis of the knee. The New England Journal of Medicine, 347 , 81–88.

Price, D. D., Finniss, D. G., & Benedetti, F. (2008). A comprehensive review of the placebo effect: Recent advances and current thought. Annual Review of Psychology, 59 , 565–590.

Shapiro, A. K., & Shapiro, E. (1999). The powerful placebo: From ancient priest to modern physician . Baltimore, MD: Johns Hopkins University Press.

Research Methods in Psychology Copyright © 2016 by University of Minnesota is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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Ideas for Psychology Experiments

Inspiration for psychology experiments is all around if you know where to look

Psychology experiments can run the gamut from simple to complex. Students are often expected to design—and sometimes perform—their own experiments, but finding great experiment ideas can be a little challenging. Fortunately, inspiration is all around if you know where to look—from your textbooks to the questions that you have about your own life.

Always discuss your idea with your instructor before beginning your experiment—particularly if your research involves human participants. (Note: You'll probably need to submit a proposal and get approval from your school's institutional review board.)

At a Glance

If you are looking for an idea for psychology experiments, start your search early and make sure you have the time you need. Doing background research, choosing an experimental design, and actually performing your experiment can be quite the process. Keep reading to find some great psychology experiment ideas that can serve as inspiration. You can then find ways to adapt these ideas for your own assignments.

15 Ideas for Psychology Experiments

Most of these experiments can be performed easily at home or at school. That said, you will need to find out if you have to get approval from your teacher or from an institutional review board before getting started.

The following are some questions you could attempt to answer as part of a psychological experiment:

• Are people really able to "feel like someone is watching" them ? Have some participants sit alone in a room and have them note when they feel as if they are being watched. Then, see how those results line up to your own record of when participants were actually being observed.
• Can certain colors improve learning ? You may have heard teachers or students claim that printing text on green paper helps students read better, or that yellow paper helps students perform better on math exams. Design an experiment to see whether using a specific color of paper helps improve students' scores on math exams.
• Can color cause physiological reactions ? Perform an experiment to determine whether certain colors cause a participant's blood pressure to rise or fall.
• Can different types of music lead to different physiological responses ? Measure the heart rates of participants in response to various types of music to see if there is a difference.
• Can smelling one thing while tasting another impact a person's ability to detect what the food really is ? Have participants engage in a blind taste test where the smell and the food they eat are mismatched. Ask the participants to identify the food they are trying and note how accurate their guesses are.
• Could a person's taste in music offer hints about their personality ? Previous research has suggested that people who prefer certain styles of music tend to exhibit similar  personality traits. Administer a personality assessment and survey participants about their musical preferences and examine your results.
• Do action films cause people to eat more popcorn and candy during a movie ? Have one group of participants watch an action movie, and another group watch a slow-paced drama. Compare how much popcorn is consumed by each group.
• Do colors really impact moods ? Investigate to see if the  color blue makes people feel calm, or if the color red leaves them feeling agitated.
• Do creative people see  optical illusions  differently than more analytical people ? Have participants complete an assessment to measure their level of creative thinking. Then ask participants to look at optical illusions and note what they perceive.
• Do people rate individuals with perfectly symmetrical faces as more beautiful than those with asymmetrical faces ? Create sample cards with both symmetrical and asymmetrical faces and ask participants to rate the attractiveness of each picture.
• Do people who use social media exhibit signs of addiction ? Have participants complete an assessment of their social media habits, then have them complete an addiction questionnaire.
• Does eating breakfast help students do better in school ? According to some, eating breakfast can have a beneficial influence on school performance. For your experiment, you could compare the test scores of students who ate breakfast to those who did not.
• Does sex influence short-term memory ? You could arrange an experiment that tests whether men or women are better at remembering specific types of information.
• How likely are people to conform in groups ? Try this experiment to see what percentage of people are likely to conform . Enlist confederates to give the wrong response to a math problem and then see if the participants defy or conform to the rest of the group.
• How much information can people store in short-term memory ? Have participants study a word list and then test their memory. Try different versions of the experiment to see which memorization strategies, like chunking or mnemonics, are most effective.

Once you have an idea, the next step is to learn more about  how to conduct a psychology experiment .

Psychology Experiments on Your Interests

If none of the ideas in the list above grabbed your attention, there are other ways to find inspiration for your psychology experiments.

How do you come up with good psychology experiments? One of the most effective approaches is to look at the various problems, situations, and questions that you are facing in your own life.

You can also think about the things that interest you. Start by considering the topics you've studied in class thus far that have really piqued your interest. Then, whittle the list down to two or three major areas within psychology that seem to interest you the most.

From there, make a list of questions you have related to the topic. Any of these questions could potentially serve as an experiment idea.

Use Textbooks for Inspiration for Psychology Experiments

Your psychology textbooks are another excellent source you can turn to for experiment ideas. Choose the chapters or sections that you find particularly interesting—perhaps it's a chapter on  social psychology  or a section on child development.

Start by browsing the experiments discussed in your book. Then think of how you could devise an experiment related to some of the questions your text asks. The reference section at the back of your textbook can also serve as a great source for additional reference material.

Discuss Psychology Experiments with Other Students

It can be helpful to brainstorm with your classmates to gather outside ideas and perspectives. Get together with a group of students and make a list of interesting ideas, subjects, or questions you have.

The information from your brainstorming session can serve as a basis for your experiment topic. It's also a great way to get feedback on your own ideas and to determine if they are worth exploring in greater depth.

Study Classic Psychology Experiments

Taking a closer look at a classic psychology experiment can be an excellent way to trigger some unique and thoughtful ideas of your own. To start, you could try conducting your own version of a famous experiment or even updating a classic experiment to assess a slightly different question.

Famous Psychology Experiments

Examples of famous psychology experiments that might be a source of further questions you'd like to explore include:

• Marshmallow test experiments
• Little Albert experiment
• Hawthorne effect experiments
• Bystander effect experiments
• Robbers Cave experiments
• Halo effect experiments
• Piano stairs experiment
• Cognitive dissonance experiments
• False memory experiments

You might not be able to replicate an experiment exactly (lots of classic psychology experiments have ethical issues that would preclude conducting them today), but you can use well-known studies as a basis for inspiration.

Review the Literature on Psychology Experiments

If you have a general idea about what topic you'd like to experiment, you might want to spend a little time doing a brief literature review before you start designing. In other words, do your homework before you invest too much time on an idea.

Visit your university library and find some of the best books and articles that cover the particular topic you are interested in. What research has already been done in this area? Are there any major questions that still need to be answered? What were the findings of previous psychology experiments?

Tackling this step early will make the later process of writing the introduction  to your  lab report  or research paper much easier.

Ask Your Instructor About Ideas for Psychology Experiments

If you have made a good effort to come up with an idea on your own but you're still feeling stumped, it might help to talk to your instructor. Ask for pointers on finding a good experiment topic for the specific assignment. You can also ask them to suggest some other ways you could generate ideas or inspiration.

While it can feel intimidating to ask for help, your instructor should be more than happy to provide some guidance. Plus, they might offer insights that you wouldn't have gathered on your own. Your instructor probably has lots of ideas for psychology experiments that would be worth exploring.

If you need to design or conduct psychology experiments, there are plenty of great ideas (both old and new) for you to explore. Consider an idea from the list above or turn some of your own questions about the human mind and behavior into an experiment.

Before you dive in, make sure that you are observing the guidelines provided by your instructor and always obtain the appropriate permission before conducting any research with human or animal subjects.

Frequently Asked Questions

Finding a topic for a research paper is much like finding an idea for an experiment. Start by considering your own interests, or browse though your textbooks for inspiration. You might also consider looking at online news stories or journal articles as a source of inspiration.

Three of the most classic social psychology experiments are:

• The Asch Conformity Experiment : This experiment involved seeing if people would conform to group pressure when rating the length of a line.
• The Milgram Obedience Experiment : This experiment involved ordering participants to deliver what they thought was a painful shock to another person.
• The Stanford Prison Experiment : This experiment involved students replicating a prison environment to see how it would affect participant behavior. 

Jakovljević T, Janković MM, Savić AM, et al. The effect of colour on reading performance in children, measured by a sensor hub: From the perspective of gender .  PLoS One . 2021;16(6):e0252622. doi:10.1371/journal.pone.0252622

Greenberg DM, et al. Musical preferences are linked to cognitive styles . PLoS One. 2015;10(7). doi:10.1371/journal.pone.0131151

Kurt S, Osueke KK. The effects of color on the moods of college students . Sage. 2014;4(1). doi:10.1177/2158244014525423

Hartline-Grafton H, Levin M. Breakfast and School-Related Outcomes in Children and Adolescents in the US: A Literature Review and its Implications for School Nutrition Policy .  Curr Nutr Rep . 2022;11(4):653-664. doi:10.1007/s13668-022-00434-z

By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book."

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In order to access this I need to be confident with:

Prob. distribution

Experimental prob.

Experimental probability

Here you will learn about experimental probability, including using the relative frequency and finding the probability distribution.

Students will first learn about experimental probability as part of statistics and probability in 7 th grade.

What is experimental probability?

Experimental probability is the probability of an event happening based on an experiment or observation.

To calculate the experimental probability of an event, you calculate the relative frequency of the event.

Relative frequency =\cfrac{\text{frequency of event occurring}}{\text{total number of trials of the experiment}}

You can also express this as R=\cfrac{f}{n} where R is the relative frequency, f is the frequency of the event occurring, and n is the total number of trials of the experiment.

If you find the relative frequency for all possible events from the experiment, you can write the probability distribution for that experiment.

The relative frequency, experimental probability, and empirical probability are the same thing and are calculated using the data from random experiments. They also have a key use in real-life problem-solving.

For example, Jo made a four-sided spinner out of cardboard and a pencil.

She spun the spinner 50 times. The table shows the number of times the spinner landed on each of the numbers 1 to 4. The final column shows the relative frequency.

The relative frequencies of all possible events will add up to 1.

This is because the events are mutually exclusive.

See also: Mutually exclusive events

[FREE] Probability Check for Understanding Quiz (Grade 7 to 12)

Use this quiz to check your grade 7 to 12 students’ understanding of probability. 15+ questions with answers covering a range of 7th to 12th grade probability topics to identify areas of strength and support!

Experimental probability vs theoretical probability

You can see that the relative frequencies are not equal to the theoretical probabilities you would expect if the spinner was fair.

If the spinner is fair, the more times an experiment is done, the closer the relative frequencies should be to the theoretical probabilities.

In this case, the theoretical probability of each section of the spinner would be 0.25, or \cfrac{1}{4}.

Step-by-step guide: Theoretical probability

Common Core State Standards

How does this relate to 7 th grade math?

• Grade 7 – Statistics & Probability (7.SP.C.5) Understand that the probability of a chance event is a number between 0 and 1 that expresses the likelihood of the event occurring. Larger numbers indicate greater likelihood. A probability near 0 indicates an unlikely event, a probability around \cfrac{1}{2} indicates an event that is neither unlikely nor likely, and a probability near 1 indicates a likely event.

How to find an experimental probability distribution

In order to calculate an experimental probability distribution:

Draw a table showing the frequency of each outcome in the experiment.

Determine the total number of trials.

Write the experimental probability (relative frequency) of the required outcome(s).

Experimental probability examples

Example 1: finding an experimental probability distribution.

A 3- sided spinner numbered 1, \, 2, and 3 is spun and the results are recorded.

Find the probability distribution for the 3- sided spinner from these experimental results.

A table of results has already been provided. You can add an extra column for the relative frequencies.

2 Determine the total number of trials.

3 Write the experimental probability (relative frequency) of the required outcome(s).

Divide each frequency by 110 to find the relative frequencies.

Example 2: finding an experimental probability distribution

A normal 6- sided die is rolled 50 times. A tally chart was used to record the results.

Determine the probability distribution for the 6- sided die. Give your answers as decimals.

Use the tally chart to find the frequencies and add a row for the relative frequencies.

The question stated that the experiment had 50 trials. You can also check that the frequencies add up to 50.

Divide each frequency by 50 to find the relative frequencies.

Example 3: using an experimental probability distribution

A student made a biased die and wanted to find its probability distribution for use in a game. They rolled the die 100 times and recorded the results.

By calculating the probability distribution for the die, determine the probability of the die landing on a 3 or a 4.

The die was rolled 100 times.

You can find the probability of rolling a 3 or a 4 by adding the relative frequencies for those numbers.

P(3\text{ or }4)=0.22+0.25=0.47

Note: P(\text{Event }A) means the probability of event A occurring.

Alternatively, it is only necessary to calculate the relative frequencies for the desired events but by calculating all of the relative frequencies and finding the sum of these values, your solution should equal 1.

The frequency of rolling a 3 or a 4 is 22+25=47.

As the total frequency is 100, the relative frequency is \cfrac{47}{100}=0.47.

Example 4: calculating the relative frequency without a known frequency of outcomes

A research study asked 1,200 people how they commute to work. 640 travel by car, 174 use the bus, and the rest walk. Determine the relative frequency of someone walking to work.

Writing the known information into a table, you have

You currently do not know the frequency of people who walk to work. You can calculate this as you know the total frequency.

The number of people who walk to work is equal to

1200-(640+174)=386.

You now have the full table,

The total frequency is 1,200.

Divide each frequency by the total number of people (1,200), you have

The relative frequency of someone walking to work is 0.3216.

How to find a frequency using an experimental probability

In order to calculate a frequency using an experimental probability:

Determine the experimental probability of the event.

Multiply the total frequency by the experimental probability.

Example 5: calculating a frequency

A dice was rolled 300 times. The experimental probability of rolling an even number is \cfrac{27}{50}. How many times was an even number rolled?

The experimental probability is \cfrac{27}{50}.

An even number was rolled 162 times.

Example 6: calculating a frequency

A bag contains different colored counters. A counter is selected at random and replaced back into the bag 240 times. The probability distribution of the experiment is given below.

Determine the total number of times a blue counter was selected.

As the events are mutually exclusive, the sum of the probabilities must be equal to 1.

This means that you can determine the value of x.

1-(0.4+0.25+0.15)=0.2

The experimental probability (relative frequency) of a blue counter is 0.2.

Multiplying the total frequency by 0.2, you have

240 \times 0.2=48

A blue counter was selected 48 times.

Teaching tips for experimental probability

• Relate probability to everyday situations, such as the chance of getting heads or tails when flipping a fair coin, to make the concept more tangible.
• Rather than strictly using worksheets, let students conduct their own experiments, such as rolling dice or drawing marbles from a bag, to collect data and compute probabilities.
• Emphasize that in mathematics, experimental probability is based on actual trials or experiments, as opposed to theoretical probability which is based on possible outcomes.
• Teach students how to record the results of an experiment systematically and use them to calculate probabilities. Use charts or tables to help visualize the data.
• Discuss events that cannot occur, such as rolling a 7 with a single six-sided die. Explain that the probability of impossible events is always 0. This helps students understand the concept of probability in a broader context.

Easy mistakes to make

• Forgetting the differences between theoretical and experimental probability It is common to forget to use the relative frequencies from experiments for probability questions and use the theoretical probabilities instead. For example, they may be asked to find the probability of a die landing on an even number based on an experiment and the student will incorrectly answer it as 0.5.
• Thinking the relative frequency is an integer The relative frequency is the same as the experimental probability. This value is written as a fraction, decimal, or percentage, not an integer.
• Assuming future results will be the same Students might think that if an experiment yields a certain probability on one day, the results will be the same the next day. Explain that while probabilities are consistent over time in theory, each set of trials can have different outcomes due to randomness, and variations can occur from day to day.

Related probability distribution lessons

• Probability distribution
• Expected frequency

Practice experimental probability questions

1. A coin is flipped 80 times and the results are recorded.

Determine the probability distribution of the coin.

As the number of tosses is 80, dividing the frequencies for the number of heads and the number of tails by 80, you have

2. A 6- sided die is rolled 160 times and the results are recorded.

Determine the probability distribution of the die. Write your answers as fractions in their simplest form.

Dividing the frequencies of each number by 160, you get

3. A 3- sided spinner is spun and the results are recorded.

Find the probability distribution of the spinner, giving your answers as decimals to 2 decimal places.

By dividing the frequencies of each color by 128 and simplifying, you have

4. A 3- sided spinner is spun and the results are recorded.

Find the probability of the spinner not landing on red. Give your answer as a fraction.

Add the frequencies of blue and green and divide by 128.

5. A card is picked at random from a deck and then replaced. This was repeated 4,000 times. The probability distribution of the experiment is given below.

How many times was a club picked?

6. Find the missing frequency from the probability distribution.

The total frequency is calculated by dividing the frequency by the relative frequency.

Experimental probability FAQs

Experimental probability is the likelihood of an event occurring based on the results of an actual experiment or trial. It is calculated as the ratio of the number of favorable outcomes to the total number of trials.

To calculate experimental probability, you calculate the relative frequency of the event: \text{Relative frequency}=\frac{\text{Frequency of event occurring}}{\text{Total number of trials of the experiment}}

Experimental Probability is based on actual results from an experiment or trial. Theoretical Probability is based on the possible outcomes of an event, calculated using probability rules and formulas without conducting experiments.

It helps us understand how likely events are in real-world scenarios based on actual data. For example, it can be used to predict outcomes in various fields such as social science, medicine, finance, and engineering.

The next lessons are

• Units of measurement
• Represent and interpret data

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• Knowledge Base

Methodology

• What Is a Controlled Experiment? | Definitions & Examples

What Is a Controlled Experiment? | Definitions & Examples

Published on April 19, 2021 by Pritha Bhandari . Revised on June 22, 2023.

In experiments , researchers manipulate independent variables to test their effects on dependent variables. In a controlled experiment , all variables other than the independent variable are controlled or held constant so they don’t influence the dependent variable.

Controlling variables can involve:

• holding variables at a constant or restricted level (e.g., keeping room temperature fixed).
• measuring variables to statistically control for them in your analyses.
• balancing variables across your experiment through randomization (e.g., using a random order of tasks).

Table of contents

Why does control matter in experiments, methods of control, problems with controlled experiments, other interesting articles, frequently asked questions about controlled experiments.

Control in experiments is critical for internal validity , which allows you to establish a cause-and-effect relationship between variables. Strong validity also helps you avoid research biases , particularly ones related to issues with generalizability (like sampling bias and selection bias .)

• Your independent variable is the color used in advertising.
• Your dependent variable is the price that participants are willing to pay for a standard fast food meal.

Extraneous variables are factors that you’re not interested in studying, but that can still influence the dependent variable. For strong internal validity, you need to remove their effects from your experiment.

• Design and description of the meal,
• Study environment (e.g., temperature or lighting),
• Participant’s frequency of buying fast food,
• Participant’s familiarity with the specific fast food brand,
• Participant’s socioeconomic status.

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You can control some variables by standardizing your data collection procedures. All participants should be tested in the same environment with identical materials. Only the independent variable (e.g., ad color) should be systematically changed between groups.

Other extraneous variables can be controlled through your sampling procedures . Ideally, you’ll select a sample that’s representative of your target population by using relevant inclusion and exclusion criteria (e.g., including participants from a specific income bracket, and not including participants with color blindness).

By measuring extraneous participant variables (e.g., age or gender) that may affect your experimental results, you can also include them in later analyses.

After gathering your participants, you’ll need to place them into groups to test different independent variable treatments. The types of groups and method of assigning participants to groups will help you implement control in your experiment.

Control groups

Controlled experiments require control groups . Control groups allow you to test a comparable treatment, no treatment, or a fake treatment (e.g., a placebo to control for a placebo effect ), and compare the outcome with your experimental treatment.

You can assess whether it’s your treatment specifically that caused the outcomes, or whether time or any other treatment might have resulted in the same effects.

To test the effect of colors in advertising, each participant is placed in one of two groups:

• A control group that’s presented with red advertisements for a fast food meal.
• An experimental group that’s presented with green advertisements for the same fast food meal.

Random assignment

To avoid systematic differences and selection bias between the participants in your control and treatment groups, you should use random assignment .

This helps ensure that any extraneous participant variables are evenly distributed, allowing for a valid comparison between groups .

Random assignment is a hallmark of a “true experiment”—it differentiates true experiments from quasi-experiments .

Masking (blinding)

Masking in experiments means hiding condition assignment from participants or researchers—or, in a double-blind study , from both. It’s often used in clinical studies that test new treatments or drugs and is critical for avoiding several types of research bias .

Sometimes, researchers may unintentionally encourage participants to behave in ways that support their hypotheses , leading to observer bias . In other cases, cues in the study environment may signal the goal of the experiment to participants and influence their responses. These are called demand characteristics . If participants behave a particular way due to awareness of being observed (called a Hawthorne effect ), your results could be invalidated.

Using masking means that participants don’t know whether they’re in the control group or the experimental group. This helps you control biases from participants or researchers that could influence your study results.

You use an online survey form to present the advertisements to participants, and you leave the room while each participant completes the survey on the computer so that you can’t tell which condition each participant was in.

Although controlled experiments are the strongest way to test causal relationships, they also involve some challenges.

Difficult to control all variables

Especially in research with human participants, it’s impossible to hold all extraneous variables constant, because every individual has different experiences that may influence their perception, attitudes, or behaviors.

But measuring or restricting extraneous variables allows you to limit their influence or statistically control for them in your study.

Risk of low external validity

Controlled experiments have disadvantages when it comes to external validity —the extent to which your results can be generalized to broad populations and settings.

The more controlled your experiment is, the less it resembles real world contexts. That makes it harder to apply your findings outside of a controlled setting.

There’s always a tradeoff between internal and external validity . It’s important to consider your research aims when deciding whether to prioritize control or generalizability in your experiment.

If you want to know more about statistics , methodology , or research bias , make sure to check out some of our other articles with explanations and examples.

• Student’s  t -distribution
• Normal distribution
• Null and Alternative Hypotheses
• Chi square tests
• Confidence interval
• Quartiles & Quantiles
• Cluster sampling
• Stratified sampling
• Data cleansing
• Reproducibility vs Replicability
• Peer review
• Prospective cohort study

Research bias

• Implicit bias
• Cognitive bias
• Placebo effect
• Hawthorne effect
• Hindsight bias
• Affect heuristic
• Social desirability bias

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In a controlled experiment , all extraneous variables are held constant so that they can’t influence the results. Controlled experiments require:

• A control group that receives a standard treatment, a fake treatment, or no treatment.
• Random assignment of participants to ensure the groups are equivalent.

Depending on your study topic, there are various other methods of controlling variables .

An experimental group, also known as a treatment group, receives the treatment whose effect researchers wish to study, whereas a control group does not. They should be identical in all other ways.

Experimental design means planning a set of procedures to investigate a relationship between variables . To design a controlled experiment, you need:

• A testable hypothesis
• At least one independent variable that can be precisely manipulated
• At least one dependent variable that can be precisely measured

When designing the experiment, you decide:

• How you will manipulate the variable(s)
• How you will control for any potential confounding variables
• How many subjects or samples will be included in the study
• How subjects will be assigned to treatment levels

Experimental design is essential to the internal and external validity of your experiment.

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Quasi-Experimental Design: Types, Examples, Pros, and Cons

Written by MasterClass

Last updated: Jun 16, 2022 • 3 min read

A quasi-experimental design can be a great option when ethical or practical concerns make true experiments impossible, but the research methodology does have its drawbacks. Learn all the ins and outs of a quasi-experimental design.

How to Craft Effective Product Experiments

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Experimentation is a powerful tool in product development. When done right, it allows teams to test assumptions, validate ideas, and gather crucial data before fully committing to a feature or change. But what does it take to design an effective experiment? In this blog post, we’ll explore the key steps to crafting product experiments and delve into various techniques you can use to ensure your experiments lead to actionable insights.

Why Crafting Experiments Matters

At the heart of experimentation lies learning. By running structured tests, you can make data-driven decisions and reduce uncertainty in product development. Experiments are particularly useful when:

• You want to validate a new feature or concept.
• You’re unsure how users will respond to changes.
• You’re exploring ways to optimize or enhance an existing product.
• You cannot make a decision for a long time
• You cannot come to an agreement with stakeholders

However, simply running experiments without careful design can lead to flawed results, wasted resources, and incorrect conclusions. That’s why crafting experiments thoughtfully is essential.

Key Steps in Crafting an Effective Experiment

1. Define Your Objective

Before jumping into experimentation, it’s critical to define what you’re trying to learn or achieve. Do you want to validate a new feature idea? Or maybe understand user preferences for a specific function? Being clear about the objective helps ensure that the experiment aligns with your product goals and prevents scope creep. At this stage, it’s also essential to decide if running an experiment is necessary. In some cases, it might be more cost-effective to build and roll out a feature directly rather than run a separate experiment. Experiments cost money too, so it’s important to weigh the cost-benefit carefully.

Example Objective: “We want to increase the number of registered users.”

2. Formulate a Hypothesis

A well-defined hypothesis gives direction to your experiment. A hypothesis should be specific, measurable, and grounded in prior knowledge. It outlines what you expect to happen and serves as a benchmark for analyzing the outcome.

Example Hypothesis: “Changing the button text to ‘Get Started’ will lead to a 15% increase in sign-ups.”

3. Choose the Right Experimentation Technique

Choosing the right technique depends on the kind of insights you’re after. Some techniques are ideal for validating early ideas with minimal investment, while others provide more in-depth user data but require more resources. We’ll explore these techniques below.

4. Identify Metrics and Success Criteria

Experiments need measurable outcomes. Identify the key metrics that will help you determine if the experiment is successful. Your success criteria should be tied to your hypothesis and objective. You need to know how to judge the results objectively without bias before you start.

Example Metrics: Sign-up conversion rate, click-through rate.

5. Design the Experiment

This step involves deciding on the structure and scope of your experiment. You’ll need to determine:

• The sample size (how many users will be part of the experiment).
• The duration (how long you’ll run the experiment).
• The control group (if applicable).
• The variables you’ll test.

For example, if you’re running an A/B test, your control group will see the existing version, while the experiment group will see the new variation.

6. Isolate Variables

It’s essential to control as many variables as possible, so the changes you make are the only factors influencing the results. This can involve randomizing user groups, ensuring representative samples, or eliminating external factors that could skew the data.

7. Run the Experiment

Launch the experiment, monitor it carefully, and make sure that your system is tracking the data correctly. It’s important not to intervene in the middle unless absolutely necessary, as that could introduce bias.

8. Analyze the Results

After the experiment, analyze the results against your success criteria. Look at whether your hypothesis was supported or disproved. Document the findings and evaluate whether further iterations are needed.

9. Learn and Iterate

One experiment often leads to the next. Even if the results weren’t what you expected, they still provide valuable insights. Maybe you noticed something unexpected or uncovered a new insight. Use these findings to craft new experiments, create a new hypothesis or refine the product based on what you’ve learned. The result of a successful experiment can also be a green light on developing an MVP version of a product or feature. Again, experiments cost resources and can negatively impact lead time to actually deliver value.

Different Techniques for Product Experimentation

Now that you understand the general process of crafting an experiment, let’s look at the various techniques you can use depending on your product stage, budget, and the type of insights you seek.

1. A/B Testing (Split Testing)

What it is: A/B testing is a simple yet powerful technique where two versions of a product or feature are tested against each other to see which performs better.

• Best For: Optimizing existing features, testing UI changes, or improving conversion rates.
• Example: Testing two different headlines on a landing page to see which one drives more clicks.

2. Multivariate Testing

What it is: Multivariate testing involves testing multiple variables at once to see how different combinations affect the outcome. It’s more complex than A/B testing but can provide deeper insights.

• Best For: Complex feature optimizations where multiple elements are changing at once (e.g., different combinations of images, headlines, and CTAs).
• Example: Testing various combinations of product images and descriptions to see which combination leads to the most purchases.

3. Usability Testing

What it is: Usability testing involves observing real users as they interact with your product to identify pain points, frustrations, and opportunities for improvement.

• Best For: Understanding user behavior and improving the user experience (UX).
• Example: Watching users navigate your website to identify confusing navigation flows or unclear elements.

4. Paper Prototyping

What it is: A low-fidelity prototype using paper sketches to simulate a digital interface. It’s an excellent early-stage technique to quickly gather feedback without developing anything.

• Best For: Early-stage concept validation, especially for new features or product ideas.
• Example: Presenting a paper version of a new app layout to potential users and gathering their feedback on usability before development.

5. Landing Page Testing

What it is: This technique involves creating a landing page for a product or feature and driving traffic to it to gauge user interest or validate a value proposition.

• Best For: Testing market demand before full product development.
• Example: Building a landing page for a new service offering and measuring sign-up intent before building the service.

6. Wizard of Oz

What it is: In a Wizard of Oz experiment, users interact with what they think is a fully functioning system, but behind the scenes, a person is manually executing the tasks.

• Best For: Testing complex product features that are not fully built yet.
• Example: Presenting a chatbot interface where, instead of AI, a team member responds manually, allowing you to test user interest before developing the actual AI.

7. Concierge MVP

What it is: The Concierge MVP involves offering a service manually rather than through an automated product. It’s used to validate whether users are interested in a feature before you invest in automating it.

• Best For: Validating demand for services or features without developing the tech upfront.
• Example: Manually helping users find product recommendations instead of developing an AI-powered recommendation engine, just to see if users value the service.

8. Pre-Order Page

What it is: A pre-order page gauges interest in a product before it’s available. Users can place an order or sign up to express interest.

• Best For: Testing the demand for a new product or feature without fully developing it.
• Example: Creating a pre-order page for a new gadget to see if there’s enough interest before mass production.

9. Feature fake/Feature stub

What it is: A fake door test involves offering a feature or product on your website or app that doesn’t exist yet. When users click to use it, they’re informed that the feature isn’t available and are invited to leave feedback.

• Best For: Testing demand for a new feature without building it.
• Example: Placing a “Try Our New Feature” button on a website to gauge interest before committing development resources.
• Caution: Excessive use can decrease the product's reputation. Some users might not use the actual feature because they believe it's still a fake.

Experiments are the foundation of evidence based product development. By carefully crafting experiments and choosing the right techniques, you can validate ideas, optimize features, and minimize risk while ensuring you’re building the right product for your users.

Different experimentation techniques allow you to test at various stages of the product lifecycle—from early-stage prototypes to fully developed features. The key is to balance cost, complexity, and insight depth as you move through each phase of development. The more experiments you run, the smarter and more efficient your product evolution becomes.

So whether you’re tweaking a small UI element or exploring a major feature, remember to experiment, measure, learn, and iterate—continuously improving your product with every test.

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