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

In this science fair project, kids start a chemical reaction that will make a balloon inflate itself!

This is a quick, easy science fair project that conveys the idea of density to upper elementary students.

In this sound experiment children listen for differences as they tap on a bag of air, a bag of water, and a wooden block held up to their ears.

In this air pressure science experiment with a balloon and a jar, children will use heat to create a partial vacuum and suck a balloon into a jar.

Using an empty tennis ball can and a swimming pool, you will determine if it's possible to have a conversation under water.

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

How does a kazoo, the strings of a guitar, or the speaker of a radio make sound? The purpose of this science fair project is to show how vibration makes sound.

Get your sense of humor ready for this fun science experiment that demonstrates the fundamental physics of air pressure.

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

This project demonstrates the correspondence between the volume of water displaced by a submerged object and the volume of the object displacing it.

In this fun science fair project idea learn about universal solvents and solutes and find out the solubility of several common liquid substances.

This science fair project creates a visual model of whatâs happening to sound waves as a car approaches and then leaves.

Put your second grade scientist to work this Fourth of July with our colorful "liquid fireworks" project!

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 rust form? Kids will learn about the roles oxygen, water, and electrons play in rust chemistry in this cool science fair project idea.

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

What is elasticity? Students will investigate how this concept applies to bouncing ball physics by testing the bounces of balls made out of different materials.