Determine which kind of rock (igneous, sedimentary, metamorphic) has the greatest reservoir capacity, which is the ability to hold the most oil and natural gas.

In this experiment, you'll make a seafloor spreading model to learn more about how plate tectonics work and create mid-ocean ridges.

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.

Magnets vary in strength. Have your young scientist figure out which kind of magnet is the strongest when you have him conduct this attractive experiment.

This science fair project idea identifies clouds as a means of predicting the weather.

Take this "paper plate snack test" with your child for a hands-on lesson in making healthier choices to teach your child about what's in his food.

Create your own cloud with an activity that will explain how important concepts such as evaporation, condensation, and precipitation work.

Ant behavior is closely related to light intensity. This free science fair project idea examines how fast ants dig when they are exposed to to light and dark.

In this fun experiment, learn about brand awareness and the influence of media on children by testing logo recognition in different age groups.

Kids discover what a homogeneous mixture is by adding sugar to distilled water and identify the various factors affecting solubility.

Is horse manure a possible energy source in a crisis? Use calorimetry to find out how much energy horse manure can produce in this science fair project.

This science fair project idea researches the effects of acid rain on plant growth.

How good are humans at sound localization? Kids can try this cool science fair project idea to see how good their friends are at judging sound direction.

The objective this science fair project is to determine whether a bigger bag will allow a homemade hot air balloon to fly higher than smaller bag.

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.

The objective of this science fair project is to test the growth rate of a plan in a crystal medium in comparison to traditional soil.

The purpose of this science fair project is to explore whether UV light passes through some colors and not others by looking at blue, red, purple, and clear.

What is a wedge? Kids find out by experimenting with different wedges in this simple science fair project idea.

This science fair project idea examines the reason boats are shaped and engineered.

In this game, players will learn interesting facts about animal adaption and practice them using a fun matching card game!

Explore if planting seeds in a certain direction will affect how fast it germinates.

Construct and experiment with a periscope using reflected light rays to gather an image.

Here is a cool and easy science project to determine the rate of chlorophyll breaks down and how it affects the color change of grass from green to yellow.

How sensitive is your skin? Here's a fourth grade science experiment that lets your child figure it out.