Learn how to make an anemometer with step-by-step instructions in this cool science fair project idea for 4th grade.

Create safe lightning for kids! They'll learn how to make lightning at home with this fun science fair project idea illustrating static charges and grounding.

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?

This recipe makes bubbles that not only blow up nice and big, but do tricks and experiments! How do you do it? It's not a secret, it's science!

Kids learn how to prevent erosion by growing grass. They'll test soil with grass against raw soil in this revealing science fair project idea for 4th grade.

Demonstrate how you can make your own compass using a magnetized needle. It also allows you to compare magnetic north and geographic north.

Experiment with buoyancy to learn how a submarine rises and sinks in this classic science experiment.

In this experiment you observe and determine how well your cat uses his whiskers to navigate through a maze.

Children will learn why and how to compost as they help with the process of filling their compost, turning it, and observing the changes that occur.

The objective of this science fair project idea is to determine if sound travels best through the air, water or a solid.

In this science experiment, your child will test the strength of hollow structures in order to understand how strong bird bones really are.

This science fair project explains the process of how the lungs expand and contract with the help of the diaphragm.

In this activity, you'll not only make your own bouncy balls at home, but your child will also learn how polymers are made.

For this science fair project, kids will learn how to make a lemon battery. They can conduct this classic experiment using readily available materials.

How do mirrors work? What is light, and how does it travel? Explore light and reflection with your preschooler with these simple hands-on experiments.

Do hand soaps and sanitizers prevent the growth of bread mold? If so, why? Kids will find out with this fun and informative science fair project idea.

In this free science fair project, learn how to separate salt from water using heat. A great science project for elementary school kids.

This classic children's game demonstrates how sound travels through air vs. through a solid.

How do organic materials become soil? This science experiment measures what materials biodegrade.

Learn the basic structure of a DNA strand, which is the double helix, how genes form together, and the resemblance DNA has to a twisted ladder. Create a model.

How do you tell time without a watch? Use the sun! This simple activity will show your child how to build his own sundial.

Learn how to make a hygrometer to measure relative humidity in this project. Make a sling psychrometer hygrometer with gauze, thermometers, and a bottle.

In this cool experiment, learn how to find specific gravity of minerals using liquids of different densities to see which substances and items sink and float.