Inspire your child to put on her engineer hat for the day, as she builds her very own, double-decker bridge.

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

This science fair project idea produces varying pitches of sound.

This science fair project demonstrates the principles of reflection through simple experiments involving mirrors and light.

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.

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

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 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.

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.

Students pit the heat capacity of water against the heat capacity of oil while looking at the effects of dipole rotation 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.

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.

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 science fair project examines how tsunamis travel by simulating a tsunami moving around an island. You will generate a pretend tsunami in a swimming pool.

Learn with makes water molecules work with this fun and easy science activity!

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.

Explore the chemistry of latex polymers with this outrageous, hilarious science activity.

Deck the halls with last season's Christmas lights for a spectacular and electrifying science activity.

This easy aerodynamics activity is a simple way to introduce kids to the scientific method.

Help your child understand the scientific concept of evaporation with this fun outdoor science activity.

Engineers in training can get started with this simple wheel-and-axle construction activity.

Along with being an interesting science activity, dehydrated strawberries are also tasty â and healthy!