This science fair project on testing water hardness is a great introduction to practical chemistry. Test and learn the difference between hard and soft water.

In this free science fair project idea, we learn about surface tension and how it can support mass—in this case, a floating paper clip.

In this simple circular motion experiment, you'll observe tangential velocity and learn about how acceleration and centripetal force affect an object.

Would your child like to learn about a hidden world? All she needs to do is open her box of markers!

Show your fourth grader how to see her heart in action. Make a simple device out of a drinking straw and clay to help her spot the movement of her pulse!

Using scherenschnitte, your science-savvy second grader will be able to create and display each part of a vegetable!

Invite your third grader to do taste test science to observe how a strawberry tastes when it is paired with various condiments. The results may be surprising!

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.

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

This experiment examines whether storing your orange juice at different temperatures affects its acidity.

This science fair project idea studies which kind of rock (sedimentary, igneous, or metamorphic) is most damaged by frozen water.

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

In this experiment, your child will create two compost bins and see if he can determine what attracts fruit flies.

The goal of this science fair project is to analyze differences between the taste and texture of frozen and fresh food.

This science fair project idea produces varying pitches of sound.

Will storing cucumbers and tomatoes in the fridge destroy their unique flavors? Find out in this science fair project idea!

This science project uses Mohsâ Hardness Test to show kids how to compare the hardness of different types of minerals.

Prove that the Earth is not flat. The objective of this science fair project is to measure the angle of the sun and calculate the circumference of the Earth.

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

This science fair project idea explores whether color affects a person's emotional state.

This science fair project idea investigates if fats add to the flavor of food.

Science fair project which determines whether it is numerically possible to be connected to every person on the earth within six degrees of separation.

In this science fair project, learn how a mineral streak is made and how it can help identify an unknown mineral.

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

This science fair project idea highlights decomposition rates by comparing how long it takes an item to decompose in a compost pile vs. a landfill.

This activity challenges your student to use spatial reasoning and computational thinking to program multiple robots.

Believe it or not, the common spud has enough electrochemical energy to power a small digital clock.

This science fair project idea explores which fruit molds the fastest.

Step into the fantastic world of colors with a project that explores what shade you -- and your friends -- like best.

This science experiment has students test whether a snail moves faster on concrete or dirt.