In this science and engineering activity, children will explore types of tunnels and their purposes and then design and build a tunnel of their own.

Challenge your learner to design and build a city of their own in this creative engineering activity.

In this activity, children will work on their mathematics and engineering skills as they attempt to recreate the Eiffel Tower out of building blocks!

Have your child build a model of a coral polyp, one of the tiny animals that composes a coral reef.

Have your child build his own mini waterfall, and help him develop his planning, problem solving, and architectural skills.

Help your child get a grasp on what it was like to build gigantic ancient structures with this easy engineering activity about science and physics.

In this activity, children will let their imagination run wild as they design and build a new planet in the solar system.

How do you tell time without a watch? Use the sun! This simple activity will show your child how to build his own sundial.

Kids build a desert food chain, desert food web, and desert food pyramid in this cool science fair project to learn about trophic levels and consumers.

Your fourth grader will be astonished to discover the significance and intricacies of his spine as he builds a model of a human vertebral column.

Future engineers, unite! Discover how to keep a sandcastleâs bridge from falling into the moat.

This science fair project idea develops an understanding through experimentation of which shapes are the most structurally strong.

In this design challenge, your child will create a parachute for a small toy using typical household items.

What is it about a Slinky that causes it to walk down the steps? This simple experiment is a perfect illustration of both gravity and momentum.

In this science fair project, apply the principles of leverage and force by building six simple machines designed to set weights in motion.

Learn how to make a ping pong ball anemometerâa device used to measure wind speedâin this free science fair project idea.

Amaze your kids by separating a salt and pepper mixture using an "electric spoon" charged with wool.

This science fair project idea experiments with spinning color wheels and optical illusions.

Have your child kick off their summer vacation by making a miniature water slide!

This science project has students collect wood samples and invent new uses for different types of wood based on its properties.

In this activity, your learner will be challenged to create their own tic-tac-toe grid out of building blocks.

This science fair project idea highlights decomposition rates by comparing how long it takes an item to decompose in a compost pile vs. a landfill.

This science fair project demonstrates the magic of arches by challenging students to stack telephone books on top of eggs without breaking them.

4th graders construct an ocean food web to learn about consumers and trophic levels, food webs, and food chains in this cool ecology science fair project.

This science fair project on testing water hardness is a great introduction to practical chemistry. Test and learn the difference between hard and soft water.

In this activity, your child will be challenged to create a device that protects an egg when it is dropped from a height of about 10 feet.

Create a DIY Electromagnet! Using a 9v battery to create an electrical field around a nail, students explore electromagnetism in this cool science project idea.

In this activity your child will create their very own marble maze!

Students will investigate the thermal conductivity of metals by learning how to measure thermal conductivity with this fun and easy science fair project idea.

In this fun science fair project, make two different scale models of our solar system using Astronomical Units and planets' relative size!