Wondering how we know that air is there? Here's a quick and easy experiment that proves that air may be thin, but it's not too wimpy to block your shot!

This science fair project idea provides evidence that air is everywhere and takes up space.

The goal of this science fair experiment is to demonstrate the effects of air pressure on objects and analyze applications of air pressure principles.

Get your sense of humor ready for this fun science experiment that demonstrates the fundamental physics of air pressure.

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.

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

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

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 air pressure science experiment with a balloon and a jar, children will use heat to create a partial vacuum and suck a balloon into a jar.

Marshmallows are made of sugar, water, and air pockets. Since the marshmallow is flexible, will air pressure cause it to expand when heated in a microwave?

This homemade barometer allows your little scientist to contemplate and compare different air and weather conditions.

Take to the air with science by experimenting with helicopter seeds right in your own backyard!

Clouds are formed when warm and cold air meet. Here's a way for kids to see it all up close!

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

This cool science fair project teaches kids about temperature, density and buoyancy using balloons that float with normal air. No helium required!

The objective of this science fair project idea is to determine if sound travels best through the air, water or a solid.

This science fair project idea demonstrates how air resistance contributes to denser objects falling faster than less dense objects.

These flying potato poppers make a cool sound, create a celebratory mood, and they can teach your child about the power of air pressure.

Do you think you could walk around upside down -- with your feet in the air and your head on the ground?

In this sound experiment children listen for differences as they tap on a bag of air, a bag of water, and a wooden block held up to their ears.

Help your child create a working lung model that fills with air just like the lungs inside of his own chest when he breathes.

Air invisible; it doesn't make sounds; you can't pick it up and throw it. So how do we know it exists? Help your second grade scientist figure it out.

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

Make your own helicopter using a paper clip and a sheet of paper. Hold the spinner up in the air, let it go, and watch it spin gracefully to the ground.

Science fair project that examines what causes thunder and why a thunderclap sounds so loud. How is lightening related to the creation of sound waves?

Does your child always demand to know why the sky is blue, how the sun moves across the sky, or where wind comes from?

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

Teach your kids about entropy with this fun, easy exercise, and teach your money to dance while you're at it!

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

Here's a fun activity that will introduce your fourth grader to the concept of frictionless motion by constructing a hovercraft.