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

Help your child get a grasp on what it was like to build gigantic ancient structures with this easy engineering activity about science and physics.

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

This simple "how to make a water wheel" activity makes physics come alive for your child by demonstrating how different kinds of energy work.

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

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.

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

Let your fourth grade chef mix up butter and sugar with scientific principles about different states of matter, and get delicious toffee, too.

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.

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

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.