This science fair project idea produces varying pitches of sound.

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

This experiment will explore how mallets of various materials and weight create sonic tones of varying lengths.

Explore the wave-particle duality of light! Learn how light can behave as both a wave and a particle in this cool physics science fair project idea for kids.

What is the Doppler Effect, or the Doppler Shift? The purpose of this science fair project is to determine how distance impacts the Doppler Effect.

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

How fast does light travel in different mediums? Kids conduct a cool refraction experiment in materials like water and air for this science fair project.

In this physics project, learn about the relationship between light intensity and distance using a laser pointer, flashlight, and graph paper!

In this cool sound resonance experiment, learn about frequency and pitch, and use a tuning fork to calculate sound velocity in air.

Design a hearing protection device to protect their ears from loud noises. Examine the properties of current protective hearing devices, 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.

In this cool science fair project, kids apply basic algebra to learn how to make a PVC pipe instrument while exploring concepts like frequency and resonance.

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

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

The goal of this science fair project is to evaluate the effect of heat on sound wave frequency.

In this science fair experiment, students learn about the scientific principles behind Doppler ultrasound.

Demonstrate how we are able to locate sounds, echolocation. Have a blindfolded subject locate you by the sound of your clapping.

The purpose of this science fair project is to build a basic radio.

Little scientists will make inferences about hearing loss, pitch, and frequency in this great science fair idea that puts the human ear to the test.

This awesome diffraction grating experiment puts high school students' applied math skills to the test by having them calculate the wavelength of laser light.

Find out the differences (if any) in the frequencies of voices produced from a computer, from a phone, and directly coming out of the voice box of a human.

Make stunning pendulum waves and learn the math behind the patterns generated with this cool and easy science project.