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

Learn about magnifying glasses, concave lenses and inverted images by sending rays of light through a magnifying glass in this cool science fair project!

In this science fair project, you'll make a "ghost" appear in a test tube, and learn about what happens when hot water and cold water interact.

Discover whether a metal will expand under hot water.

Check out this fun and easy 4th grade science fair project idea that tests how gravity induces positive and negative geotropism (gravitropism) in bean plants.

In this experiment, young ecologists will learn about a type of edge effect: how trees and plants at the edge of a forest can act as a weed filter.

Determine whether butterflies like to drink sugar water, salt water, or plain water.

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

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

Science fair project that examines how to grow bacteria in a controlled setting, using simple materials from around the home.

This cool and easy elementary school science fair project idea provides the basic information on the use of our senses to experience the world about us.

Science fair project that examines condensation and the conditions needed in order for dew to form.

Free science fair project idea that examines the differences between cats and dogs. Analyze objective qualities rather than subjective ones.

In this science fair project, apply the principles of leverage and force by building six simple machines designed to set weights in motion.

This science project has students collect wood samples and invent new uses for different types of wood based on its properties.

Prove that the Earth is not flat. The objective of this science fair project is to measure the angle of the sun and calculate the circumference of the Earth.

The objective of this science fair project is to examine the basic principles of air pressure using simple materials like a balloon, straw and string.

Is it amplitude? Weight? Length of string? Kids will discover what factors changing the period of a pendulum depends on in this fun and easy physics experiment.

In this experiment you explore how tectonic plates move to create land and expand bodies of water.

What causes the seasons to change? Kids find out by modeling the earth's tilt using a globe, flashlight and graph paper in this cool science fair project idea.

examine how passive solar heating works, measure temperature in a parked car on a sunny day. ways to use passive solar heating as an alternative, energy

Science fair project that determines whether cooling eggs helps them be peeled more easily. Compare the time it took to peel each egg.

What's the difference between a microwave and an oven? Use mashed potatoes to explore which kitchen appliance does a better job at keeping food warm.

Test out the pH levels of soil in your backyard versus soil in more wild environments to solve this science case.

What's the chemistry behind dyeing Easter eggs? Will adding vinegar to dye help the eggshell absorb the color? This colorful science project has the answers!

Kids will learn how to make a steam powered rocket boat, also called a putt putt boat or a pop pop boat, in this great science fair project for 4th graders.

In this fun science fair project idea, kids will experiment with various methods in order to discover the fastest way to cool a soda.

Future engineers, unite! Discover how to keep a sandcastleâs bridge from falling into the moat.

This light bulb science project includes step-by-step instructions for testing the heat from different light bulbs.

This science fair project idea determines which method of hand cleansing is the most effective.