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.

In this cool science experiment, learn about magnetism and poles, and test magnet strength to find out if two magnets are twice as strong as one.

In this experiment, students find out what happens when a less-dense fluid interacts with a denser one, replicating the effect of cooler solid rock on magma.

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

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

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

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

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

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

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.

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

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!

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

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.

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

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.

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.

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.

What is a compound microscope? Kids find out by making one of their own in this cool science fair project.

Have your child build a model of a coral polyp, one of the tiny animals that composes a coral reef.

This science fair project looks one of the most important factors affecting seed germination: water. A fun and easy plant biology experiment for 3rd graders.

Observe how your brain works while it is focused on one thing, and how it works while you are distracted by another thing.

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!

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

The goal of this science fair project is to discover the science behind carbonated soft drinks and apply this knowledge to create a new one.

Science fair project which tests various sedimentary, igneous and metamorphic rocks to find out whether one rock family is stronger than the others.

You don't need to wait for rain to see a rainbow. Make one yourself, and teach your child about light and weather in the process.

Show your kids the power of baking powder by conducting a simple experiment. Make four batches of cornbread, all identical except for one thing: baking powder!