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

This project compares the strength of one, two, and three-ply toilet paper.

In this investigation, three different juices are tested to determine which juice contains the greatest amount of vitamin C.

The rock cycle will come alive for your child when he uses broken crayons to create the three basic rock types.

Examine which metal conducts more heat by boiling water in 3 pans made of aluminum, copper, and stainless steel.

In this cool project, create a lighted, scale model of the different layers of the Sun, including the core, radiation and convection zones, and photosphere.

Make your own marshmallows and mix up some very interesting third grade chemistry lessons while you're at it!

Crystals are a very special structure. In this third grade activity, your child will learn how to grow salt crystals.

First grade science often covers solids, liquids, and gases. This silly science explores serious facts about the difference between all three.

This interdisciplinary card game will have your third grader working on math facts as he travels through the solar system!

Observe with your third grader what happens when food starts to decompose, and boost science skills simultaneously with this experiment!

Learn about different fern fronds with your third grader as you create lacy, natural decorations on your Easter eggs this year.

If your science savy third grader is up for a challenge, let her bend light with a casserole dish!

Help your fifth grader trace your family's roots and interview all the living mothers to create a makeshift, 3-D family tree!

Your third grader will be amazed at the explosive combination of vinegar and baking soda in these chocolate volcano cupcakes with white chocolate "lava."

Create a three-dimensional X-ray of your child's hand in this simple modeling activity. All you need to get started are black paper and drinking straws

Help your curious third grader construct a dazzling spinning wheel that will teach him about the science behind colors while providing some silly entertainment!

In this open-ended activity, students will be given a small quantity of three types of materials and asked to design a prototype for “something that will improve the school.”

Explore the craters, maria, and highlands on the surface of the Moon! In this fun science project you'll create a 3-D model of the moon using paper mache.

Wool can absorb 1/3 of its weight in water, while still keeping the body warm. She can test this theory by performing a scientific sock comparison!

Here is a hands-on activity to help third graders understand the four points of a compass...and how we use them to get around.

This craft is a great way to explore the fascinating world of spiders and their webs as you collect spider webs from around your house with your third grader.

Your third grader will delight in learning about sound waves as he observes the different sounds created by tapping on glasses with varying amounts of water.

Want to spark your third grader's interest in gardening? Help him make popsicle stick fairies to decorate an enchanting garden oasis.

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!

Encourage a group of third graders to play this fun game of Whistle Hide-and-Seek as a warm-up to get them prepared for finding a "lost" camper.

Bring a little science to your third grader's Christmas as you test out his sense of smell by exposing him to common Christmas scents found in your kitchen.

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.

Experiment with buoyancy to learn how a submarine rises and sinks in this classic science experiment.