Try this simple activity with your middle schooler to help him develop an understanding of why scientific classification systems exist and how they work.

Here's how you and your teen can stage your own formal debateâbeyond arguing why chores are unethical! Formal debates improve teens' critical thinking skills.

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

What if the shape of the Earth weren't spherical? How does its shape affect our gravity, climate, and tides? Model these questions in this cool project!

Learn about our response to scents that existed in our environment over evolutionary time and consider why scents might affect our mood state.

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

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

Easy and cool middle school science fair project on ripening process of fruits and measures you can take to prevent fruits from rotting and delay ripening.

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.

Look for correlation between pH values of commercial soaps and detergents and manufacturer claims about eye irritation hazards.

The objective of this science fair project is to analyze the effects of salinity and temperature on water.

What causes dilated pupils? Young scientists will find out by applying what they already know about changes in pupil size and making models of the pupil.

Science fair project that evaluates how well clothing fabrics block UV radiation by examining the properties of different fabrics.

Use a microscope in this experiment to learn about different kinds of "good bacteria" that turn milk into yogurt!

This fun science fair project idea helps students learn how acid rains are formed and explore how acid rain damages the environment.

Why does purple cheese look nasty? Because color plays a big part in how we perceive the taste of different foods. Are birds just like us in this respect?

This simple "how to make a water wheel" activity makes physics come alive for your child by demonstrating how different kinds of energy work.

Can you plant the insect-attracting borage plant to increase the amount of beneficial insects in your garden? Find out in this experiment!

Science fair project that examines the behavior of water and gravel in creek beds and the formation of sedimentary rocks.

Science fair project which compares the rates of photosynthesis for various light sources. Which type of light will be best for photosynthesis and why?

Fudge is one of very few desserts people make at home that is actually crystalline. What happens when the fudge crystallizes at different temperatures?

Science fair project which evaluates different athletic shoes in order to find out whether any of them affect a person's ability to run.

The objective of this experiment is to find out if cooked beans grow faster, if at all, than uncooked beans.

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

This science fair project idea creates cool new colorful fabric pattern designs and experiments with the mixing of colors.

Science fair project that determines the correlation between the ability of selected materials to conduct heat and a material's density.

How can you tell the difference between a spider and an insect? Your child will find out as he makes a tray of yummy creepy crawly snacks.

This balloon-powered car project is a great way for your kid to learn about energy and how it can be used efficiently.

Does the temperature of a magnet affect its strength? Learn about the relationship between magnets and temperature with this cool physics science fair project.

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.