Water, along with soil and light, is a necessary component for plant growth. So what's better for promoting plant growth: tap water, or rain water?

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.

Glass is see-through, but usually you can still see that it is there. In this experiment, we use baby oil to make glass go completely invisible.

What causes the seasons to change? Kids find out by modeling the earth's tilt using a globe, flashlight and graph paper in this cool science fair project idea.

How does a flashlight work? Kids will make a complete circuit and explore how voltage contributes to brightness with this science fair project idea.

Kids learn how to manipulate additive and subtractive colors to send secret messages with red colored filters in this cool science fair project idea.

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.

This science fair project investigates why the number of visible stars changes from place to place.

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.

In this project, learn about animal vision and different kinds of eyes: ocelli, compound eyes, and camera eyes. Find out what a jellyfish or grasshopper sees!

What heats up fasterâwater or soil? 5th grade students test the specific heat of water against the specific heat of sand in this great science fair project.

What makes your shadow dance around all day? Let's play detective and find out why that sneaky shadow never stays in one place for long.

This science fair project idea studies which brand of wintergreen candy produces the most sparks in the dark.

Find out whether optical mice are useful on all surfaces or if there are drawbacks to this supposedly superior solution to the traditional roller-ball mouse.

Ever wonder why refrigerator lights turn off when you close the door? Does the darkness prevent food from spoiling? This experiment, determines just that.

Explore how sound waves are reflected and absorbed by producing echoes. Analyze which locations produce echoes.

This science experiment tests why guacamole goes brown and if leaving the pit in will stop guacamole from turning brown.

This science fair project idea investigates if heat from direct sunlight is hotter than heat from reflected sunlight.

What cause the phases of the moon? Make a model to see how the positions of the Sun, Moon, and Earth cause the crescent, gibbous, quarter, full, and new moon.

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

This science fair project idea investigates how color affects temperature.

This science fair project idea determines which method of hand cleansing is the most effective.

This science fair project idea researches how your choice of clothing affect how hot or cool you feel during the day.

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 science fair project, kids will be able to see where germs reside on their hands while gaining insight into the benefits of thorough hand washing.

This science fair project idea determines what household items are good conductors of electricity.

Check out this cool science project idea to learn about rocks and explore the cycles of formation, breakdown, and reformation of rocks in the Earth's crust.

This science project idea examines the effect of microwaving on various objects.

Does electricity move better through thick wires or thin ones? kids will conduct this classic electricity experiment for this science fair project.

The objective of this science fair project is to observe the differences in heat absorption for darker colors vs. lighter colors.