Learn how to make a hygrometer to measure relative humidity in this project. Make a sling psychrometer hygrometer with gauze, thermometers, and a bottle.

These science fair experiments demonstrate the chemistry of rust and the oxidation process.

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.

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.

This science fair project idea investigates if fats add to the flavor of food.

This science fair project idea investigates the difference in reaction times between boys and girls.

Check out this science project idea to compare organic produce to non-organic produce and how preservatives in food extend the shelf life of goods.

Science fair project that examines how temperature affects density and how density in turn affects the behavior of helium gas.

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

Construct batteries that make electricity from fruits with this fun science fair project.

In this microwave plant experiment, find out whether microwave radiation will affect radish seed germination. Will it help or hinder the plants' growth?

Can a horse lead itself to the carrot? Train your horse with carrots and boxes and test horse memory in this fun zoology science fair project.

Play with balance and simple engineering as you hurry to create a sturdy rock tower.

Get this cool science fair idea to explore how arctic tundra animals change their behavior and adapt to survive in long, cold winters.

Science fair project which determines whether plants are able to get enough nutrients from different types of garbage.

This experiment challenges students to forecast the weather based on the surrounding areas' weather.

Learn about the layers of the Earth and make a model! Create a earth layer book, cake, or clay diagram.

Kids learn about potential energy, and mechanical energy, and how to make power from water with one of our favorite renewable energy projects for kids.

Cleaning can be a chore, but not with this sudsy experiment!

In this enlightening transpiration experiment, kids will explore how the loss of water from plants through transpiration contributes to the water cycle.

Most people assume that cold water freezes more quickly, but could that be false? Does hot water freeze faster than cold water? Let's find out!

Do earthworms like moisture or darkness? Find out as we explore the relationship between earthworms and light.

Wiggly worms are known for staying buried in the soil, but how does that affect plants? Are earthworms and plant growth related?

When you rub a balloon on your head, your hair stands up; but is that true for everyone? Does hair color affect static electricity?

Learn how to be a bird scientist in this simple project of watching feathered friends in their habitat.

Kids learn how to prevent erosion by growing grass. They'll test soil with grass against raw soil in this revealing science fair project idea for 4th grade.

Is there a relationship between caffeine and heart rate? Students will determine the effect of caffeine on heart rate in this fun science fair project.

This science experiment examines the role of fat in food, especially in making bread rise and whipping cream.

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

How well can people recall what they have observed. Test your knowledge in this fun experiment.