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!

Magnets vary in strength. Have your young scientist figure out which kind of magnet is the strongest when you have him conduct this attractive experiment.

Create a DIY Electromagnet! Using a 9v battery to create an electrical field around a nail, students explore electromagnetism in this cool science project idea.

In this project, all you need is a protractor to learn how to use the altitude of Polaris to find latitude on Earth. Polaris is also known as the North Star.

This science fair project idea investigates how color affects temperature.

This science fair project idea explores if the length of the string that an object is suspended on has an effect on how fast or slow it swings.

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.

This science fair project idea investigates if heat from direct sunlight is hotter than heat from reflected sunlight.

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.

This science fair project examines how seeds hitchhike on animals and clothing.

This science fair project teaches kids experimental design and how to test if subjects can really sense if they are being watched.

Kids learn how to prevent erosion by growing grass. They'll test soil with grass against raw soil in this revealing science fair project idea for 4th grade.

In this science fair project, students create their own miniature salt flats at home.

This science fair project idea examines whether boys and girls differ in reflexes.

Construct and experiment with a periscope using reflected light rays to gather an image.

This science fair project idea examines whether the colors of the spectrum respond differently in the thermal aspect when radiated by the sun.

In this fun science fair project, make two different scale models of our solar system using Astronomical Units and planets' relative size!

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.

Science fair project examining barometric pressure, and how it can be used to predict the weather. How does atmospheric pressures relate to weather conditions?

In this science fair project, students make their own rain gauge to measure rainfall.

Want to see a great example of Newton's first law? Kids will learn about basic physics with this fun, ballistic experiment.

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.

How does distance affect the spreading of light? Kids see diffraction and the inverse square law of light in action with this great science fair project idea.

4th graders construct an ocean food web to learn about consumers and trophic levels, food webs, and food chains in this cool ecology science fair project.

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.

Kids build a desert food chain, desert food web, and desert food pyramid in this cool science fair project to learn about trophic levels and consumers.

This science fair project teaches students about wilting and browning of salad greens.