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.

This science fair project idea explores how length affects the weight a bridge can hold.

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

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 idea explores whether it is easier to balance on a narrow ledge or on a rope.

In this classic Ivory soap experiment, kids learn what happens to different types of soap in the microwave, and why!

This science fair project idea investigates how color affects temperature.

Did you know your body is full of simple machines? This project looks at one of the third-class levers in the human body: your arm!

In this experiment you observe and determine how well your cat uses his whiskers to navigate through a maze.

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

This science fair project idea investigates how optical distances change the apparent size of an object as seen through a magnifying lens.

Using a toy race car kids create a visual model of the Doppler Effect.

This science fair project idea investigates the difference in reaction times between boys and girls.

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

Find out whether soil amendments can improve soil conditions and help you grow a bigger beanstalk in this ecology experiment!

Kids construct a single fixed pulley system to learn how pulleys can make work easier in this cool physics and engineering science fair project idea.

Demonstrate how static electricity can cause an object to move. It also examines just how an object affected by static electricity will move.

This science fair project idea explores substances that cause a bubble to last longer.

This science fair project idea investigates how the shape of an object affects drag.

This science fair project idea investigates if webbed feet help a duck (and others) swim.

This science fair project idea teaches how the gases and pollution in the air affect the earth's atmosphere temperature.

This classic children's game demonstrates how sound travels through air vs. through a solid.

This classic children's game-connecting two cups with a string-demonstrates sound's ability to travel through air vs through a solid.

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

What is a compound microscope? Kids find out by making one of their own in this cool science fair project.

What keeps a an item cooler, polymer crystals or ice? Find out in this cool science experiment!

This science fair project uses paper chromatography to investigate whether black, brown, orange, and purple are pure colors or mixtures of other colors.

Find out whether a longer airplane will fly farther or a wider paper airplane.

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.