In this cool engineering science fair project, kids learn how to build Hero's engine: an enlightening example of Newton's third law.

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

In this popcorn experiment, students can explore how two things made out of the same material can have very different appearances and densities.

What's the relationship between temperature, air humidity and static electricity? Kids will find out with this free static electricity science fair project.

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

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.

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

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.

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

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

Did you ever add salt to pasta? Did it help cook the pasta faster? If not, find out in this science fair project idea.

In this science fair projects, students will grow out the bacteria that collect on air conditioner filters.

How well can people recall what they have observed. Test your knowledge in this fun experiment.

Would your dog prefer homemade or store-bought food? Raw or cooked? Test your dog's preferred diet in this fun experiment.

In this science fair project, students discover how sedimentary layers form as sediments like mud, silt and sand settle over time.

Can you increase the light and plant growth in your garden using mirrors? In this experiment, measure light reflection and find out!

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

Kids will learn about the interaction of lactose and lactase in milk and discover why we describe enzymes as catalysts in this fun science fair project.

Watch pre-packaged seeds and seeds taken from inside fruits and vegetables grow. Which ones will grow faster? Read more in this science fair project idea.

The project determines determine if a sports drink affects the heart rate of a student athlete during exercise.

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

Kids will conduct a cool limewater carbon dioxide test that can be performed with common household materials to learn about the chemistry of this common gas.

What chromosome combinations determine a fetus gender? Use probability to think about whether a sperm and ovum will create a male or female in this 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.

In this experiment, students find out what happens when a less-dense fluid interacts with a denser one, replicating the effect of cooler solid rock on magma.

These science fair experiments demonstrate the chemistry of rust and the oxidation process.

Science fair project which determines if plants really do need water to grow, or whether they just need to be kept wet.

Will potatoes spud or sprout faster in dry, dark, or cold conditions? Find out in this science fair project idea!