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

In this science fair project, apply the principles of leverage and force by building six simple machines designed to set weights in motion.

This activity provides a solution to all those leaves on your doorstep, while also giving your child a fun science lesson.

This science fair project idea is develops new or improved paper making techniques and encourages recycling.

Chemistry isn't just incredible ... sometimes its edible! These crystal lollipops are a delicious introduction to chemistry concepts.

Can you imagine a sky filled with bright, colorful bubbles? Make this whimsical scene come alive with bubble science!

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.

To help your child learn how to use a thermometer, try this temperature collecting activity at home.

In this activity, you'll not only make your own bouncy balls at home, but your child will also learn how polymers are made.

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.

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 experiment you explore how tectonic plates move to create land and expand bodies of water.

Here's a fun science experiment that's refreshingly tasty too! Turn regular water into a tasty treat perfect for consuming on a hot day.

Make your own helicopter using a paper clip and a sheet of paper. Hold the spinner up in the air, let it go, and watch it spin gracefully to the ground.

examine how passive solar heating works, measure temperature in a parked car on a sunny day. ways to use passive solar heating as an alternative, energy

Young scientists will investigate people's preferences for saltiness, and make some inferences about genetics and diet.

Science fair project that determines whether cooling eggs helps them be peeled more easily. Compare the time it took to peel each egg.

Here's a classic celery science experiment that uses celery and food coloring to demonstrate how plants absorb water.

This science fair project idea examines whether plants are still able to grow normally if they are turned upside-down.

This science fair project idea examines liquids of different densities.

The project determines which laundry detergent is best for cleaning clothes.

In this classic Ivory soap experiment, kids learn what happens to different types of soap in the microwave, and why!

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.

For this science fair project, kids will learn how to make a lemon battery. They can conduct this classic experiment using readily available materials.

This science experiment tests if dog saliva can really help heal wounds.

In this activity, your child will transform an egg into a glowing, bouncy "ball" that they can play with.

What's the difference between a microwave and an oven? Use mashed potatoes to explore which kitchen appliance does a better job at keeping food warm.

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

This project explores whether plants can live and grow when "watered" with juice, soda, or milk.

Kids construct a single fixed pulley system to learn how pulleys can make work easier in this cool physics and engineering science fair project idea.