This science fair project idea produces varying pitches of sound.

This science fair project idea experiments with spinning color wheels and optical illusions.

This science fair project idea produces sounds by creating vibrations using different objects.

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.

This science fair project idea explores whether talking to a plant will help it grow.

This science fair project idea investigates which objects float and sink in honey, water, and oil.

In this science fair project, young children discover what happens when two fluids that have different densities get together.

This science fair project idea explores the relationship between oil and water in terms of density as well as hydrophilic/hydrophobic compounds.

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.

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

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

Science fair project that examines what causes thunder and why a thunderclap sounds so loud. How is lightening related to the creation of sound waves?

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.

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 does the size of a vibrating surface affect the pitch of a drum? Learn about drum size and pitch with this easy science fair project idea.

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

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.

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.

Discover whether different amounts of water added into a wine glass will produce a different pitch when their fingers are rubbed along the rim.

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.

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

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.

Observe how your brain works while it is focused on one thing, and how it works while you are distracted by another thing.

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

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.