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.

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.

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.

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 a toy race car kids create a visual model of the Doppler Effect.

Take a closer look at your furry friend (or the furry friend of a neighbor -- with permission) to discover if communication exists between cats and humans.

This play-activity causes young children to focus on and become more aware of their sense of hearing and the power of their ears.

Can you dig it? This science experiment isn't for kids who like to keep their hands clean.

It's rhyme time! With this science fair project idea, your child will find out which words can be considered easy rhyming words, and why.

Do you think you could walk around upside down -- with your feet in the air and your head on the ground?

Start your toy engines -- this is going to be a fast and friction-filled race!

Kids will learn how to show the direction of magnetic field lines and create a permanent model using iron filings in this great science fair project idea.

Do earthworms like moisture or darkness? Find out as we explore the relationship between earthworms and light.

The objective of this science fair project is to examine the effects of temperature on salt and water solutions, as they form crystals over time.