What's the best way to make DIY compost? Kids will learn about aerobic and anaerobic decomposition while learning to appreciate the value of composting.

In this experiment, kids will see if pruning tomato plants makes them more fruitful and learn about the factors that contribute to a plant's fruit production.

In this science and engineering activity, children will explore types of tunnels and their purposes and then design and build a tunnel of their own.

Kids will conduct a cool limewater carbon dioxide test that can be performed with common household materials to learn about the chemistry of this common gas.

How does a compass work? What's a magnetic field? Kids will build their own compass at home to find the answers in this great science fair project idea.

Is it possible to trick the forces of nature that make your bubbles round to create a square bubble?

What are the effects of fertilizer on plant growth? What's the best fertilizer type (solid, liquid or powder)? Kids find out in this science fair project idea.

In this fun science project, learn about what happens to cut fruit and experiment with how to stop apples from turning brown.

Learn about savanna flora and fauna in this science project! Take a look at characteristics of tropical grassland plants and animals that help them survive.

This science fair project looks one of the most important factors affecting seed germination: water. A fun and easy plant biology experiment for 3rd graders.

What are buttress roots? In this fun science project, make a model of a rainforest tree and learn how they help trees survive in the tropical rainforest!

In this enlightening transpiration experiment, kids will explore how the loss of water from plants through transpiration contributes to the water cycle.

In this cool science fair project idea, kids conduct the ruler drop test on volunteers to determine whether reaction time can be improved with practice.

In this simple circular motion experiment, you'll observe tangential velocity and learn about how acceleration and centripetal force affect an object.

In this activity, your child will be asked to create a boat that can successfully float while holding 25 pennies.

This science fair project idea determines if the color of light affects the growth of plants.

How well can people recall what they have observed. Test your knowledge in this fun experiment.

Want to see a great example of Newton's first law? Kids will learn about basic physics with this fun, ballistic experiment.

When you rub a balloon on your head, your hair stands up; but is that true for everyone? Does hair color affect static electricity?

Science fair project about work and energy which uses a simple mathematical formula to predict how far a jar will roll down an incline.

Check out this fun and easy 4th grade science fair project idea that tests how gravity induces positive and negative geotropism (gravitropism) in bean plants.

Test out the pH levels of soil in your backyard versus soil in more wild environments to solve this science case.

Science fair project that teaches you about chemical indicators and how to make your own in order to identify various mystery solutions.

How does smell affect taste? Ready your taste buds--in this project, you'll gather some test subjects and do a taste test to see how much smell affects taste.

These science fair experiments demonstrate the chemistry of rust and the oxidation process.

Kids will learn how to make a thermometer to to explore liquid density in this great science fair project. Which liquids are affected by temperature the most?

Kids will learn about the interaction of lactose and lactase in milk and discover why we describe enzymes as catalysts in this fun science fair project.

4th graders construct an ocean food web to learn about consumers and trophic levels, food webs, and food chains in this cool ecology science fair project.