This science fair project idea demonstrates that light travels in straight lines and experiments with reflecting light.

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.

Science fair project which determines whether people are more likely to follow rules if they are easy to understand.

In this science project, baking powder and vinegar are used to simulate the action of a fire extinguisher.

Science fair project determines relationship between number and variety of insects and spiders by collecting and counting invertebrates in a ecosystem.

You've heard all about oil spills, but can they really be that bad? After all, vegetable oil is in almost every yummy baking good from cookies to brownies.

In this simple science project, learn about what causes dew and what affects dew formation with a drinking glass, ice, and a soda bottle.

In this CD hovercraft science project, students will construct their own DIY hovercraft.

This science fair project idea explores how enzyme inhibitors, active sites, non-competitive enzyme inhibitors, and substrates work.

Learn how to make a hygrometer to measure relative humidity in this project. Make a sling psychrometer hygrometer with gauze, thermometers, and a bottle.

Would it hurt to skip brushing your teeth just this once? Let's find out by seeing which foods produce the most mouth bacteria.

Kids will create their own version of Richard Feynman's rubber band heat engine to learn about thermodynamics with this cool science fair project idea.

What animals are most popular? This project affords practice in data-collection, record-keeping and data-analysis through the investigation of this question.

Demonstrate how you can make your own compass using a magnetized needle. It also allows you to compare magnetic north and geographic north.

Kids make a paperclip perform an act of magnetic levitation and test how effective various materials are at magnetic shielding in this science fair project.

Science fair project which measures the shadow cast by a meter stick at various times in order to predict the circumference of the earth.

This science fair project demonstrates the magic of arches by challenging students to stack telephone books on top of eggs without breaking them.

Learn how to make an anemometer with step-by-step instructions in this cool science fair project idea for 4th grade.

What does a raindrop look like when it splashes on the ground? Is each raindrop unique like snowflakes? Find out how raindrop size varies in this experiment.

What are the effects of colored light on plant growth? Explore plant behavior in this cool botany science fair project and learn about phototropism!

How clean is the air we breathe? The answer might surprise you. Learn how to investigate local air quality with this cool science fair project.

This science fair project idea explores plant growth from a bulb, root, and a stem and investigates asexual plant reproduction.

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.

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

Soil and energy don't go together, right? That would be as bizarre as a pairing of peanut butter and marshmallows! Well, actually...

Learn how to make a ping pong ball anemometerâa device used to measure wind speedâin this free science fair project idea.

This science fair project idea investigates how the height at which a pendulum is released affects the length of time it continues.

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

Soil is made up of different layers. How far down do you need to dig to find the soil horizon, or the place where bits of leaves and branches become soil?

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