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.

Will increasing the amount of salt in water effect how slow or fast the water freezes?

This science experiment tests whether warm or cold water works best in making cut flowers last longer.

Kids will learn how to make a thermometer to to explore liquid density in this great science fair project. Which liquids are affected by temperature the most?

Kids will make a beautiful rainbow in a jar and learn what enables different types of liquids to remain distinct in separate layers.

The moon doesn't produce its own light, so why can we see it shining in the sky? Learn about reflection and planetshine in this fun and easy science project!

Using a toy race car kids create a visual model of the Doppler Effect.

Ever wondered how a plant drinks water? This science project will teach you how and help you create a beautiful floral display!

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

Learn how to tell time by the sun with this cool science fair project idea that tracks how the accuracy of a sundial changes over time.

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

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

Step into the fantastic world of colors with a project that explores what shade you -- and your friends -- like best.

Take a closer look at your furry friend (or the furry friend of a neighbor -- with permission) to discover if communication exists between cats and humans.

In this free science fair project, build a star clock and learn how to tell time on a clear night by observing the big dipper!

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

This science fair project idea compares biodiversity between drops of water.

How does frost form? How fast does it form? Do this simple science project using a plastic glass, rock salt and some water to learn about deposition.

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

In this fun science experiment, kids will determine the best method for ripening avocados and discover the cool chemical reaction that makes this possible.

This easy and inexpensive paper towel science project introduces kids to important physical concepts like cohesion, adhesion, and capillarity.

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.

The goal of this evaporation experiment is to learn about how different external conditions affect drying time.

Is it magic? No...it's the amazing, gravity-defying capillary action experiment! Kids will love this dramatic and enlightening science fair project.

Understanding absorption means understanding why certain fibers and materials can absorb water! Kids will see absorption in action in this simple project.

Learn about the role of Earth's rotation on the Coriolis Effect and hurricanes in this science project. Model the Coriolis Effect on a hurricane's direction.

Children have a naturally inquisitive mind. Foster their curiosity with a walk through an autumn field or park to answer age-old “why” questions. As you walk with your child, you can encourage them to ask questions.

What's the best way to make DIY compost? Kids will learn about aerobic and anaerobic decomposition while learning to appreciate the value of composting.

In this experiment, kids will see if pruning tomato plants makes them more fruitful and learn about the factors that contribute to a plant's fruit production.

How does the size of a vibrating surface affect the pitch of a drum? Learn about drum size and pitch with this easy science fair project idea.