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

Collect meteorite dust with a magnet in your very own backyard! The objective of this science fair project is to gather meteorite dust to study outer space.

Discover flight initiation distance as you play around in the park with this fun bird watching project!

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

Do you think heat can affect a plant's growth rate?

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

Have you ever seen fruit decay? Find out if a fruit will rot faster if you open it versus leaving it untouched!

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

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

Saturn is the ringed planet in our solar system, a gas giant with rings made of ice and dust. Let's make a cool scale model with an old CD and some glitter!

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.

This science fair project idea examines liquids of different densities.

In this project, a model of a submarine is built to simulate the buoyancy and displacement of water and air.

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

This is a quick, easy science fair project that conveys the idea of density to upper elementary students.

Find out whether putting something on top of a plant will inhibit its growth.

In this project, you'll build a model of the earth, complete with all seven continents and four major oceans.

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.

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

Check out this fun and easy 4th grade science fair project idea that tests how gravity induces positive and negative geotropism (gravitropism) in bean plants.

What is persistence of vision? With this hands-on science fair project idea, students will demonstrate this cool and dramatic phenomenon in their own classroom.

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

The project determines the forces that cause paper airplanes to fly and determine which type of paper airplane flies the farthest.

This science fair project idea explores how the shape of a boat affects its density and how much weight it can float.

This is a fantastic and easy science experiment where kids will learn about elasticity by testing how high bouncy balls of different materials can bounce.

Kids will learn how to make a steam powered rocket boat, also called a putt putt boat or a pop pop boat, in this great science fair project for 4th graders.

This science fair project idea examines whether the colors of the spectrum respond differently in the thermal aspect when radiated by the sun.

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.