Has your child ever asked you how a submarine works? Here's a simple bathtub project that will make for a hands-on answer.

How do the phases of the Moon and gravity cause spring tides and neap tides? Does the Sun play a role in the tides? Figure it out in this fun science project!

Is it amplitude? Weight? Length of string? Kids will discover what factors changing the period of a pendulum depends on in this fun and easy physics experiment.

We all know that the Moon has different phases, but it can be hard to figure out why. Try this activity to see how the Moon's phases really work.

Got a birdwatcher on your hands? Bring the birds to your backyard by making a zany bird feeder using an orange and some string.

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.

This science fair project idea examines whether plants are still able to grow normally if they are turned upside-down.

In this project, you'll create Oersted's experiment, which relates to how electric currents create magnetic fields.

Help your child add some flair to the family garden with pencil pinwheels!

Make a periscope with milk cartons and mirrors! This preschool activity is great for playing secret agent and learning simple physics.

Have your child make a special mobile inspired by the weather outside. Learn about seasons, the environment, and art in 3D.

This project explores how well couples convey complex emotions such as envy and pride to one another solely through the sense of touch.

Science fair project that determines how your mirror image differs from your actual image and how virtual images are constructed.

The goal of this science fair project is to attempt to build a perpetual motion machine and analyze the Laws of Thermodynamics.

Kids construct a single fixed pulley system to learn how pulleys can make work easier in this cool physics and engineering science fair project idea.

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 optics-based science fair project idea teaches kids about real and virtual images with a mind-bending candle illusion inspired by Pepper's Ghost.

Science fair project that examines learn how the angle of incidence affects the efficiency of solar panels. How does a solar cell work?

Explore convex and concave objects and how they reflect light.

Kids make strong bubbles to investigate the effect different additives have on bubble life in this cool science fair project idea.

In this science project, young children observe, record, and create collections of colors in their world and increase their powers of observation.

In this science fair project, young children observe, record, and create collections of shapes in their world and increase their powers of observation.

In this science fair project, students use hot and cold water to simulate what happens when a warm front meets a cold one.

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

This science fair project idea explores what it takes to create a biosphere, or a self-sustaining ecosystem.

Do this activity to help your kids see how seeds contain "baby" versions of big plant stems, roots, and leaves.

In this project children practice the scientific method while playing with puffy paint.