Do plants get crowded? Have your curious kid investigate how plants respond if they're forced to grow together in a confined space.

This is a quick, easy science fair project that conveys the idea of density to preschool and early elementary children.

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

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.

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

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

Play with balance and simple engineering as you hurry to create a sturdy rock tower.

In this fun science experiment, kids will determine the best method for ripening avocados and discover the cool chemical reaction that makes this possible.

When you rub a balloon on your head, your hair stands up; but is that true for everyone? Does hair color affect static electricity?

Do you think you can blow down a sand castle with a mighty wind? Find out which material stands up best to erosion in this erosion experiment.

Learn about the layers of the Earth and make a model! Create a earth layer book, cake, or clay diagram.