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58 Science Projects for 3rd Graders

58 Science Projects for 3rd Graders

Looking for ways to develop a lifelong love of learning in 3rd graders? Our handpicked list of 3rd grade science projects is designed to do just that!

Wall Color and Indoor Temperature
1. Wall Color and Indoor Temperature
Paint five boxes different colors, place them in sunlight, and discover which color traps the most heat inside.
Medium
Sugar Water and Cut Flower Freshness
2. Sugar Water and Cut Flower Freshness
Place roses, carnations, and lilies in vases with different amounts of sugar water and track which combination keeps them fresh the longest.
Medium
Pinto Beans in Cotton vs. Soil
3. Pinto Beans in Cotton vs. Soil
Plant pinto beans in cotton balls and three types of soil. See which growing material produces the tallest plants over six weeks.
Easy
Paper Airplane Folds and Flight Distance
4. Paper Airplane Folds and Flight Distance
Fold paper airplanes with different designs and launch them to discover which shape flies the farthest.
Medium
Rainbow Borax Crystals
5. Rainbow Borax Crystals
Grow sparkling rainbow crystals overnight on pipe cleaners and watch solid crystal structures form as the Borax water cools.
Medium
Paper Cup Anemometer for Wind Speed
6. Paper Cup Anemometer for Wind Speed
Attach four paper cups to crossed cardboard strips and count spins to estimate wind speed outdoors.
Medium
Raisins Rising and Sinking in Fizzy Water
7. Raisins Rising and Sinking in Fizzy Water
Drop raisins into a jar of vinegar and baking soda and watch them rise, float, and sink over and over again.
Easy
Scratch Testing and Rock Hardness
8. Scratch Testing and Rock Hardness
Scratch rocks with everyday objects like coins and nails to rank their hardness on the Mohs scale.
Medium
Bubble Additives and Lasting Power
9. Bubble Additives and Lasting Power
Add one secret ingredient to a soap bubble solution and discover which one keeps bubbles floating nearly six times longer than plain soap.
Medium
Smell and Taste Connection
10. Smell and Taste Connection
Blindfold volunteers and plug their noses to discover how much harder it is to identify foods.
Easy
Reflexes and Reaction Time
11. Reflexes and Reaction Time
Drop a ruler and use a conversion chart to turn the catch distance into your exact reaction time in milliseconds.
Easy
Body Dominance Across Hand, Foot, Eye, and Ear
12. Body Dominance Across Hand, Foot, Eye, and Ear
Test whether right-handed people also favor their right side for kicking and listening.
Easy
Seashells and Vinegar
13. Seashells and Vinegar
Place one seashell in vinegar and another in water, then check back in a week to see which one dissolves.
Easy
Static Electricity and Jumping Cereal
14. Static Electricity and Jumping Cereal
Rub a plexiglass plate with wool and watch Rice Krispies leap off the table and stick to the charged surface.
Easy
Elephant Toothpaste Foam Reaction
15. Elephant Toothpaste Foam Reaction
Pour a yeast mixture into a bottle of hydrogen peroxide and watch a giant column of warm foam erupt.
Easy
Play-Doh Solar System to Scale
16. Play-Doh Solar System to Scale
Shape Play-Doh into scale-sized planets and discover how tiny Earth looks next to Jupiter.
Easy
Borax Geode Crystals
17. Borax Geode Crystals
Turn a hollow eggshell into a miniature geode by growing Borax crystals inside it overnight.
Medium
Sugar Crystallization and Rock Candy
18. Sugar Crystallization and Rock Candy
Grow giant sugar crystals on a string and watch a supersaturated solution turn back into solid rock candy.
Medium
Vinegar Fizz Test for Calcite in Rocks
19. Vinegar Fizz Test for Calcite in Rocks
Drop vinegar on a rock and watch for fizzing bubbles that reveal hidden calcite inside.
Easy
Candy Models of Rocks and Minerals
20. Candy Models of Rocks and Minerals
Cut open different candies and classify them as rock or mineral models based on what the inside looks like.
Easy
Grass vs. Bare Soil Under Heavy Rain
21. Grass vs. Bare Soil Under Heavy Rain
Pour water over a grass-covered trough and a bare-soil trough on a slope, then compare how much dirt washes away.
Medium
Pinhole Viewer from a Cereal Box
22. Pinhole Viewer from a Cereal Box
Poke a tiny hole in a cereal box and see the world projected upside-down on a waxed paper screen inside.
Medium
Sunlight Shadows on Living Leaves
23. Sunlight Shadows on Living Leaves
Clip cardboard shapes onto living leaves for four days and uncover a visible record of where sunlight was blocked.
Easy
Salt Water Concentration and Plant Damage
24. Salt Water Concentration and Plant Damage
Water identical plants with different salt concentrations each day and track which level causes the most damage over 15 days.
Easy
Milk vs. Water for Growing Tomatoes
25. Milk vs. Water for Growing Tomatoes
Water one pot of tomato seeds with milk and another with water to discover which liquid actually helps plants grow.
Easy
White Daisies and Food Coloring
26. White Daisies and Food Coloring
Place white daisies in colored water and watch the petals change to blue or red within a single day.
Easy
Planting Depth and Bean Seed Sprouting
27. Planting Depth and Bean Seed Sprouting
Bury bean seeds at four depths and find out how deep is too deep for a sprout to emerge.
Easy
Radish Growth and Daily Water Volume
28. Radish Growth and Daily Water Volume
Give ten pots of radish seeds different daily water amounts and find the range that produces the tallest plants in ten days.
Medium
Balloon Power and Newton's Third Law
29. Balloon Power and Newton's Third Law
Tape a balloon to a Styrofoam car and watch Newton's Third Law launch it across the floor.
Medium
Baking Soda Invisible Ink and Grape Juice
30. Baking Soda Invisible Ink and Grape Juice
Write a secret message with baking soda water and reveal it by painting grape juice over the paper.
Easy
Lemon Juice Invisible Ink and Heat
31. Lemon Juice Invisible Ink and Heat
Write an invisible message with lemon juice and watch your hidden words appear in brown when you add heat.
Medium
Oobleck and Non-Newtonian Fluids
32. Oobleck and Non-Newtonian Fluids
Squeeze a simple mix of cornstarch and water into a solid ball, then open your hand and watch it flow back into a liquid.
Easy
Water Temperature and Convection
33. Water Temperature and Convection
Drop food coloring into three jars of different temperature water and watch the color spread at wildly different speeds.
Medium
Trapped Air and Atmospheric Weight
34. Trapped Air and Atmospheric Weight
Tie an air-filled bag over a jar and press down, then try pulling an empty bag out of a sealed jar to feel atmospheric weight.
Easy
Eggshell Arches and Load-Bearing Strength
35. Eggshell Arches and Load-Bearing Strength
Cut four eggs into domes and stack books on top to see how much weight the arches can hold.
Easy
Ants and Light vs. Darkness
36. Ants and Light vs. Darkness
Set up two ant observatories and discover whether ants dig more tunnels in the dark or in the light.
Medium
Moon Phases with Cookie Models
37. Moon Phases with Cookie Models
Scrape the filling from sandwich cookies to model all eight Moon phases and see how the sunlit portion changes.
Easy
Vinegar and the Rubbery Egg
38. Vinegar and the Rubbery Egg
Drop a raw egg into vinegar for a few days and discover that the acid dissolves the hard shell, leaving behind a soft, rubbery egg.
Easy
Chocolate and the Rock Cycle
39. Chocolate and the Rock Cycle
Use chocolate shavings and heat to build three types of model rock that match real geology.
Medium
Fruit-Sized Planets and Solar System Scale
40. Fruit-Sized Planets and Solar System Scale
Pick a fruit to match each planet's size and line them up to see how the solar system is spaced out.
Easy
Capillary Action Walking Rainbow
41. Capillary Action Walking Rainbow
Connect cups of colored water with paper towels and watch capillary action build a complete rainbow overnight.
Easy
Galaxy in a Jar with Glitter and Paint
42. Galaxy in a Jar with Glitter and Paint
Swirl glitter and paint in a jar of water to create a miniature galaxy that sparkles when you shake it.
Easy
Dish Soap and Milk Color Bursts
43. Dish Soap and Milk Color Bursts
Touch a soap-dipped cotton swab to food coloring in milk and watch the colors burst apart into swirling patterns.
Easy
Household Solar System Model
44. Household Solar System Model
Turn a balloon into the Sun and shape play dough planets to build a tabletop solar system model.
Easy
Pocket Solar System to Scale
45. Pocket Solar System to Scale
Fold a strip of paper into a pocket-sized model that shows the real distances between the Sun and each planet.
Medium
Earth and Sun Size Comparison Model
46. Earth and Sun Size Comparison Model
Build a scale model of the Sun and Earth and count how many Earths fit across its width.
Easy
Cornstarch Oobleck and Shear Thickening
47. Cornstarch Oobleck and Shear Thickening
Punch a bowl of cornstarch and water and discover a liquid that turns solid under force, then flows the moment you stop.
Easy
Starburst Candy and the Rock Cycle
48. Starburst Candy and the Rock Cycle
Reshape Starburst candies with heat and pressure to model how the Earth forms three types of rock.
Medium
Egg Drop Survival Challenge
49. Egg Drop Survival Challenge
Design a protective case from household materials and find out whether your raw egg survives a high drop.
Medium
Pre-Soaked Spaghetti and Cooking Time
50. Pre-Soaked Spaghetti and Cooking Time
Soak spaghetti in water for a few hours, then boil it for just one minute to test whether pre-soaking cuts cooking time.
Medium
Salt and Oil Density Lava Lamp
51. Salt and Oil Density Lava Lamp
Sprinkle salt onto a layer of oil over colored water and watch oil blobs get dragged down and float back up.
Easy
Red Cabbage pH Lava Lamp
52. Red Cabbage pH Lava Lamp
Add Alka-Seltzer to a red cabbage lava lamp and watch the blobs shift color as you change the pH.
Medium
Glow-in-the-Dark Lava Lamp
53. Glow-in-the-Dark Lava Lamp
Charge glow-in-the-dark paint and drop a fizzy tablet into oil to create a lava lamp that glows without a black light.
Easy
Density-Driven Alka-Seltzer Lava Lamp
54. Density-Driven Alka-Seltzer Lava Lamp
Drop an Alka-Seltzer tablet into oil and colored water and watch gas bubbles carry blobs up and down like a lava lamp.
Easy
Glitter Lava Lamp with Antacid Tablets
55. Glitter Lava Lamp with Antacid Tablets
Drop an antacid tablet into a bottle of oil, water, and glitter to create a sparkling lava lamp that keeps cycling.
Easy
Baking Soda and Vinegar Lava Lamp
56. Baking Soda and Vinegar Lava Lamp
Drop baking soda and vinegar into a bottle of oil and water and watch colored blobs rise and sink like a real lava lamp.
Easy
Seed Sprouting on a Paper Towel
57. Seed Sprouting on a Paper Towel
Place kitchen seeds on a damp paper towel and watch roots and shoots appear within days as germination unfolds.
Easy
Sun Prints on Construction Paper
58. Sun Prints on Construction Paper
Lay leaves and flowers on construction paper in the sun to reveal sharp, colorful outlines where UV rays cannot reach.
Easy

3rd Grade Science Project FAQ

What are some easy 3rd grade science fair projects?

Any one of these easy 3rd grade science fair projects will teach you important scientific concepts and help you have fun while learning. An easy science fair project is a great way to introduce the wonders of science to 3rd graders!

  • Preserving Flowers with Sugar

  • Bacteria on Our Hands

  • Growing Your Own Yeast Fungus

  • Magic Milk Painting

  • Swimming Raisins

  • Making Oobleck: Liquid or Solid?

  • Sparkling Rainbow Crystal

  • Explosive Elephant Toothpaste

  • Colors of Skittles Experiment

  • Balancing a Ball in Air

Science fair project details right above the FAQ!

What is the best 3rd grade science project ever?

We love the Bacteria on Our Hands science fair project for 3rd graders. It's a great way to introduce 3rd graders to bacteria, tiny living things we can't see until we grow a bunch of them on a special plate called an agar plate.

If you're looking for more 3rd grade science projects, check out the 3rd grade science fair projects at the top of this page! 

Check out more Best Science Fair Projects →

What are some cool 3rd grade science fair projects?

Get ready to be amazed by these super cool science projects for 3rd graders! With just a few simple things, you can be fascinated by science and have tons of fun with these cool 3rd grade science projects!

  • Bacteria on Our Hands

  • Magic Milk Painting

  • Swimming Raisins

  • Making Oobleck: Liquid or Solid?

  • Sparkling Rainbow Crystal

  • Explosive Elephant Toothpaste

  • Preserving Flowers with Sugar

  • Growing Your Own Yeast Fungus

  • Balancing a Ball in Air

  • Colors of Skittles Experiment

Science fair project details right above the FAQ!

What are 5 testable questions for 3rd grade?

A testable question is a question that we can answer through a science experiment. To do this, we do a control science experiment, then we change one thing in the experiment to see how it affects what happens. This is how we can discover the answer to our question!

  • What makes a cloud form?

  • Can drink and food taste different just by changing its color?

  • Does the color of light affect photosynthesis?

  • Does temperature affect seed sprouting?

  • What makes popcorn pop?

Here are more testable questions along with their science projects →

What are the top 10 science projects for 3rd grade?

These are our top 10 science projects for 3rd grade, with projects from Biology, Chemistry, Physics, Engineering and Earth Science. These projects can be used as science fair project ideas or as a fun experiment to explore different areas of science!

  • Colorful Temperature

  • Preserving Flowers with Sugar

  • Bacteria on Our Hands

  • How Soil Affects Pinto Bean Growth

  • Growing Your Own Yeast Fungus

  • Jiggly Earth: Exploring Liquefaction

  • Growing Crystals in Different Temperatures

  • Make Your Own Anemometer

  • Balancing a Ball in Air

  • Swimming Raisins

Science project details right above the FAQ!

Can I do a 3rd grade science fair project in a day?

Yes! Quick experiments can be a great option for a science fair project! If you want to explore quick reactions, we have science project ideas on various topics to get you started.

  • Acid-base reactions: Mixing acids with bases quickly makes carbon dioxide gas!

Make a rocket fly sky high with just baking soda and vinegar! Rocket Film Canisters

  • Chromatography reactions: Separate out colors!

Did you know that some Skittles have a secret rainbow hiding inside them? Colors of Skittles Experiment

  • Heat reactions: Heat speeds things up!

Do you want to find out which color candle burns the fastest? Which Candle Burns the Fastest?

What are some hands-on ways to find inspiration for my science fair project?

Science museums are great places to explore if you're looking for inspiration for your next science fair project or just want to learn more about science. Science museums, natural history museums, space museums, and discovery museums are all great places to do that! You can discover all sorts of interesting things about science and find cool project ideas for science fairs.

There may be free admission days or free passes to a science museum near you! Check your local library for free museum passes, nearby science museums for free entrance days and your credit card for offers.

Find a science museum near you and prepare to be awed by all that you can learn there! I always learn something new and am inspired whenever I go to a science museum!

How do I start a science fair project?

Science fair projects are a fun and unique way to discover science by asking a question and doing a science project. We'll help you find a science fair project idea and guide you through the process of doing and presenting your science fair project with Science Fair Coach's Science Fair Project Guide.

What should I do after I have a science fair project idea?

If you have a science fair project idea, Science Fair Coach can help you turn it into a full science fair project! Starting at Introduction to Science Fairs, we'll guide you through how to do a science fair project, from designing and conducting your experiment to collecting and analyzing your findings. Then, we'll help you showcase your results on a science fair board with our Guide to Science Fair Posters.

How do I make a science fair board?

Your science fair board is where you show off your science fair project for everyone to see and learn from. With our Guide to Science Fair Posters, you can make sure your science fair board stands out and impresses at the science fair!

What is the scientific method?

The 7 steps of the scientific method helps us understand how nature works. Learn how the scientific method is used in a science fair project example, and how it's evolved through history as scientists used different ways to learn about nature with our Guide to the Scientific Method!

What is the engineering design process?

The 6 steps of the engineering design process helps us design an effective solution to a problem. Learn how to use the engineering design process with the example of the egg drop challenge in our Guide to the Engineering Design Process!

Where can I find a science fair competition?

Science fair competitions are an excellent opportunity to explore science. One of the of the premier science advocacy organizations, the Society for Science, is associated with more than 400 science fair competitions in almost every US state, as well as over 70 other countries, regions, and territories. You can find out if there's a Society of Science affiliated science fair near you!

The www Virtual Library: Science Fairs website also has a collection of science fairs from all over the world, as well as national, state, regional, local, and virtual competitions!

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