STEM
Grades:
4th Grade

50 Exciting Hands-On Fourth Grade Science Experiments, Activities, and Projects

Did you know you can make plastic from milk?

4th grade science projects including creating a groovy blue lava lamp out of a water bottle and building a wigglebot out of a red plastic cup.

Nothing gets kids more excited for science than hands-on experiments! Watch your fourth grade science students’ eyes light up when they try some of these activities. You’ll find physics, biology, engineering, chemistry, and more. These projects are easy to set up and really help drive the learning home. Get ready for some science fun!

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1. Flick marbles to learn transfer of energy

Fourth grade science student flicking a marble along the ridge in a ruler

This experiment is a bit of a thinker: What will happen when one moving marble hits several stationary marbles sitting in a row? Flick the first marble and find out!

Learn more: Frugal Fun for Boys and Girls/Marble Energy Transfer

2. Measure a magnet’s attraction force

Small magnet, paper clip, ruler, and instruction card

Fourth grade science students already know that magnets attract metal objects. In this experiment, they’ll measure to see how close a magnet needs to be to an object for the attraction to work. Mix things up with different sizes of magnets and objects of various weights.

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Learn more: Ashleigh’s Education Journey

3. See light refraction in action

Student dipping a drawing into a glass of water, using light refraction to make the color disappear

This seems more like a magic trick, but we promise it’s science! Make colors seem to appear and disappear, change numbers into letters, and more.

Learn more: Ronyes Tech

4. “Draw” on water with dry-erase marker

Student pouring water onto a clear glass plate with rainbows drawn on it with dry erase marker

This is another one of those mind-blowing science demos that kids will want to try over and over again. Draw on a shallow bowl or plate with dry-erase markers, then slowly add water. The marker (which is insoluble in water) will float to the top!

Learn more: Active Littles

5. Paint with sunscreen

Sun painted onto a piece of black construction paper using sunscreen

Prove that sunscreen really does provide protection from harmful UV rays. Turn this into a full-blown experiment by trying different SPFs or comparing it to other creams or lotions without SPF.

Learn more: Team Cartwright

6. Blow unpoppable bubbles

Student's gloved hand holding a soap bubble next to a window (Fourth Grade Science)

A soap bubble you can hold in your hand? It’s true! A little glycerin makes the soap bubble layers stronger, so you can even toss them gently from person to person.

Learn more: Learning Resources

7. Grow crystal names

Crystalized pipe cleaner letters A, k, e, and m

No list of fourth grade science experiments would be complete without crystals! Kids of all ages love growing crystals, making this an ideal way to learn about supersaturated solutions. The classic experiment gets a new twist when you have kids shape pipe cleaners into their own names first.

Learn more: Playdough to Plato

8. Engineer a drinking-straw roller coaster

Student building a roller coaster of drinking straws for a ping pong ball (Fourth Grade Science)

STEM challenges are always a hit with kids. We love this one, which only requires basic supplies like drinking straws. (Get more fourth grade STEM challenges here.)

Learn more: Frugal Fun for Boys and Girls

9. Make a wigglebot

Plastic cup turned into a simple wiggling robot with markers for feet (Fourth Grade Science)

Who knew electricity could be so adorable? Explore the science behind batteries and motors by creating a simple “wigglebot.” Experiment with weights to throw the motor off balance and create fun designs.

Learn more: Research Parent

10. Grow bacteria in petri dishes

Six petri dishes growing a variety of molds and bacteria

Your students will truly feel like scientists when they perform this classic experiment. They’ll prep the dishes with agar, swab different surfaces, and see what bacteria they grow. It’s gross science, but it’s also easy and impressive.

Learn more: Steve Spangler Science/Growing Bacteria

11. See coastal erosion in action

Plastic bin filled with sand, shells, and water to simulate a beach, with a hand holding a plastic bottle in the water (Fourth Grade Science)

Here’s a cool experiment to include in your unit on oceans. Build a miniature coastline, then see how wave action erodes the shore.

Learn more: Little Bins for Little Hands/Erosion

12. Construct a working flashlight

Student's hand powering a flashlight made from index card, LED, foil, and masking tape

You’ll only need a few supplies to guide your students in building their own LED flashlights. They’ll learn how electricity travels and the way circuits work. The slideshow available through the link makes this lesson a breeze for teachers too.

Learn more: Mystery Science/DIY Flashlight

13. Erupt a lemon volcano

Cut lemon in a blue bowl covered in colorful fizzy foam (Fourth Grade Science)

Early chemistry experiments with acids and bases are always a lot of fun. This one uses the natural acids of lemon juice and adds a little food coloring to up the wow factor.

Learn more: STEAM Powered Family

14. Sink and float to explore density

Series of glasses filled with liquid labeled baking soda water, sugar water, control plain water, and salt water, with red and blue objects floating in each

Ask your students if any of them have ever gone swimming in the ocean and noticed that it’s easier to keep afloat there than in a pool. Then, try this experiment to learn why that happens.

Learn more: Science Kiddo

15. Discover a density rainbow

Clear glasses filled with a rainbow of liquids, and a tube showing those liquids layered on each other (Fourth Grade Science)

Colorful, simple, and impressive: It’s the trifecta of fourth grade science experiments! Wow your students by layering colored sugar water as you learn about density, adhesion, and cohesion.

Learn more: Little Bins for Little Hands/Sugar Density Rainbow

16. Become human sundials

Fourth grade science students measuring their outlines drawn in sidewalk chalk on the playground

Choose a sunny day and grab some sidewalk chalk—your students are about to become sundials! They’ll practice measuring skills and learn about the movement of the sun across the sky.

Learn more: Rhythms of Play

17. Transform milk into plastic

Green plastic heart and yellow beads made from milk caseins

Plastic seems incredibly modern, but people have been making casein plastic from milk for centuries. In this science project, students experiment to create the formula for the best milk plastic. They’ll be amazed at the results!

Learn more: Science Buddies/Milk Plastic

18. Simulate an earthquake

Fourth grade science teacher's hand shaking a pan of Jello topped with a house model made of toothpicks and marshmallows

The ground under our feet may feel solid, but an earthquake changes that pretty quickly. Use Jell-O to simulate the earth’s crust, then see if you can build an earthquake-proof structure.

Learn more: Teaching Science

19. Mine for chocolate chips

Student's hand digging through a crumbled cookie to pull out chocolate chips (Fourth Grade Science)

If you’re learning about mineral resources, this quick hands-on activity is an interesting way to explore the effects of mining. Kids have two minutes to find as many chocolate chips as they can in a cookie. Will they smash it up and destroy it entirely? Pick them out one by one? This experiment can lead to intriguing discussions.

Learn more: Sarah’s STEM Stuff

20. Assemble an edible DNA model

Student holding a DNA model made from Twizzlers, colored marshmallows, and toothpicks

Use licorice sticks, four different colored candies or fruits, and toothpicks to build an edible strand of DNA. Learn about chemical bonds and the helix shape, then eat your creation!

Learn more: wikiHow

21. Layer an edible soil model

Clear cup layered with chocolate chip bedrock, pudding subsoil, crushed cookie topsoil, and coconut grass

Digging in the dirt is fun, but it’s even more fun when you can eat the dirt when you’re finished! Create edible soil-layer models, complete with gummy worms, for a simple earth science project. (Find more edible science projects here.)

Learn more: Super Teacher Blog

22. Brew elephant toothpaste

Two liter bottle overflowing with pink foam (Fourth Grade Science)

OK, this isn’t really what elephants use to brush their teeth, but this big foamy exothermic reaction needs a big name! Wow your class using simple materials, including dish soap, hydrogen peroxide, and a packet of yeast.

Learn more: Science Bob

23. Test Sharpie solubility

Coffee filters colored with marker, dipped into vinegar, rubbing alcohol, and water

Find out if Sharpie markers are really permanent with this fourth grade science activity that uses the scientific method to explore solutes and solvents.

Learn more: Around the Kampfire

24. Build a hovercraft

Inflated yellow balloon attached to a CD by a bottle cap

It’s not exactly the same model the military uses, but this simple hovercraft is a lot easier to build. An old CD and a balloon help demonstrate air pressure and friction in this fun fourth grade science experiment.

Learn more: Education.com/DIY Hovercraft

25. Learn about capillary action

Glasses filled with colored water, with paper towels running from one to the next

Kids will be amazed as they watch the colored water move from glass to glass, and you’ll love the easy and inexpensive setup. Gather some water, paper towels, and food coloring to teach the scientific magic of capillary action.

Learn more: 123 Homeschool 4 Me/Capillary Rainbow

26. Find out if mood rings really work

Student's hand holding a blue mood ring in front of a thermometer

Apply the rigors of the scientific method to mood rings! Find out what makes mood rings change color, then see if they really reflect a person’s mood.

Learn more: Education.com/Mood Rings Validity Test

27. Create a smartphone projector

Cardboard box with a magnifying glass embedded in it, with a smart phone (Fourth Grade Science)

No projector in your classroom yet? No problem! Have your students help you construct one for your smartphone using a cardboard box and large magnifying glass. They’ll learn about convex lenses and how the brain processes images too.

Learn more: The STEM Laboratory

28. Set up a pulley system

Pulley system made of cans and yarn mounted on a piece of cardboard

The science of machines never fails to fascinate kids. In this experiment, they’ll design their own pulley system to make it easier to lift an object.

Learn more: 123 Homeschool 4 Me/DIY Pulley

29. Design a working elevator

Elevator made of paper towel tubes, dowel rods, and string

Engineering activities make for amazing hands-on learning. Challenge your students to build an elevator that can safely lift a certain amount of weight.

Learn more: Teachers Are Terrific

30. Turn a penny green

Five pennies turned various shades of green (Fourth Grade Science)

Experiment with simple chemical reactions as you turn pennies green using vinegar. Don’t forget to tell them that the Statue of Liberty is green because of the very same reasons.

Learn more: Buggy and Buddy/Penny Reactions

31. Use marshmallows to explore Boyle’s law

Fourth grade science students holding large syringes filled with colorful marshmallows

Seeing Boyle’s law (which relates pressure and volume of gasses) in action makes it a little easier to understand and remember. This simple fourth grade science experiment uses marshmallows to make a great visual.

Learn more: Hojo’s Teaching Adventures

32. Create a new plant or animal

Science project showing an imaginary plant called a Snap-a-Doodle

Kids will really get into this project, indulging their creativity as they invent a plant or animal that’s never been seen before. They’ll need to be able to explain the biology behind it all, though, making this an in-depth project you can tailor to any class.

Learn more: I Love 2 Teach

33. Form ocean currents

Glass pan full of blue and purple swirls of water, with ice cubes and plastic sea creatures

Learning about oceanography? Demonstrate how ocean currents form using warm and cold water (and a few plastic sea creatures for extra fun!).

Learn more: Life Over C’s

34. Understand the impact of non-renewable resources

Index cards with various pasta types glued to them, including rotini, rigatoni, and shells (Fourth Grade Science)

This is a neat Earth Day activity. Discuss the differences between renewable and non-renewable resources, then have your class form “companies” to “mine” non-renewable resources. As they compete, they’ll see how quickly the resources are used. It’s a great tie-in to energy conservation discussions.

Learn more: The Owl Teacher

35. Explode a Mentos geyser

Fourth grade science students looking on in amazement as diet soda shoots high into the sky from bottles

Here’s another classic for the fourth grade science experiments list: diet soda and Mentos! Everything you’ve heard about this experiment is true, so choose an outdoor location and get ready to make an enormous mess as you explore nucleation.

Learn more: Steve Spangler Science/Mentos Geyser

36. Investigate decomposition

Plastic bag containing a plate of rotting food

Yup, it’s gross … so your kids will love it! Seal food items in a plastic bag and experiment to see what factors affect their decomposition, helped along by a heaping dose of mold.

Learn more: Mystery Science/Decomposition

37. Explore blood components

Glass jars full of corn syrup, red candy, and marshmallows (Fourth Grade Science)

Use simple kitchen supplies to create a jar full of “blood” that includes plasma, platelets, red blood cells, and white blood cells. (You can even snack on the blood cells along the way!)

Learn more: Almost Supermom

38. Watch gravity beads prove Newton’s laws

Child holding a cup of blue bead strings, watching them flow out of the cup

You’ll need a loooooooong string of beads for this experiment. Make your own by taping dollar store strings together, or buy a long bead garland. Pile them in a cup and get the beads going; it’s fascinating to watch inertia and gravity at work.

Learn more: Teach Beside Me/Gravity Beads

39. Make a model seismometer

Paper cup suspended by strings, with a marker sticking out the bottom making lines on a strip of paper

Explore the science of seismology and learn how scientists study earthquakes and their effects. This model seismometer is easy to build and fun to experiment with.

Learn more: Science Sparks/Seismology

40. Conduct an egg drop

Paper straws taped around an egg in a triangle shape (Fourth Grade Science)

Here’s one more classic to add to our list of fourth grade science experiments: the egg drop! The great thing about this project is that kids can do it at any age, with different materials and heights to mix it up. Hit the link below to get an egg drop project designed just for fourth graders.

Learn more: Buggy and Buddy/Egg Drop

41. Create cool colors with candy

Skittle heart science experiment for 4th grade.

This is a quick and easy experiment for around Valentine’s Day. All you’ll need are Skittles, a pie pan, water, and a heart-shaped cookie cutter. Your students will love the display of color, and they’ll get a sweet treat as well!

Learn more: Milwaukee With Kids

42. Predict the weather

4th grade science experiment to measure the strength of the wind.

Your students can easily (an inexpensively) construct their very own anemometer to measure the strength of the wind. Simply count how many revolutions the lead cup makes per minute, and your students have just become budding meteorologists!

Learn more: The Activity Mom

43. Demonstrate Newton’s law of motion

4th grade students can demonstrate Newton's Law of Motion with balloon rockets.

Who doesn’t love balloon rockets?! Your students will have a blast(off) displaying Newton’s third law of motion while learning about physics.

Learn more: School Science Experiments

44. Model basic chemical reactions

Classic 4th grade science experiment to demonstrate basic chemical reactions.

Balloons are a fabulously inexpensive and exciting supply to use to demonstrate a ton of fun scientific principles. In this classic activity, students will learn about chemical reactions by mixing together vinegar and baking soda. It’s messy, but it’s lively!

Learn more: Sciencing

45. Simulate lung function

Simulate how lungs expand and contract with this 4th grade science experiment.

What’s this? Yet another experiment you and your students can perform with balloons! Pick up a giant pack, and lead your students in exploring how lungs perform their function as well as the basics of air pressure.

Learn more: KiwiCo

46. Predict the behavior of phosphors

Demonstrate phosphors with this bright 4th grade experiment.

Your students will ooh and aah at the result of this exploratory way to show phosphors in action with a black light, different types of water, and a highlighter. The results of this experiment might surprise both you and your students!

Learn more: Cool Science Experiments Headquarters

47. Explore the causes of tooth decay

Demonstrating the science of tooth decay

They hear it from their parents all the time, but this experiment will prove to your students once and for all what can happen to their teeth when exposed to different drinks such as sugar water, soda, and milk.

Learn more: Sciencing

48. Replicate the Dead Sea to exhibit density

Explore density using an egg and salt water.

You don’t have to take a field trip to the Dead Sea to demonstrate the principle of density! Create your own “Dead Sea” in your classroom by using salt water and an egg. Though this lab becomes rather detailed with the equations for density, you can easily adapt it to allow your students to explore the basic concepts of how less-dense solids can float in more-dense liquids.

Learn more: Science Buddies

49. Engineer kinematics with a ball run

4th graders construct a ball run to explore kinematics.

This engineering challenge not only demonstrates kinetic energy, but it will challenge your students’ engineering skills as well. They’ll work to construct a ball run with the goal of making their ball go the slowest.

Learn more: Science Buddies

50. Construct a groovy lava lamp

Homemade lava lamp for 4th grade science students.

Your students will explore the relationship between oil and water in this funky lab as well as observe a chemical reaction between an acid and a base. We imagine they’ll want to take theirs home to display as art as well!

Learn more: Education.com

Keep the STEM excitement going with these 25 Fantastic Free Fourth Grade Math Games.

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Watch your fourth grade science students' eyes light up when they try some of these activities. Make crystals, build a pulley, and more.