One of the most popular science fair models based on the celestial sky would be that of the Solar System. The Sun with its planets in orbit around it is not only easy to make, but is also fun to learn. This easy project is ideal for elementary school science fair projects.

Getting the different sized balls to explain the difference between the sizes of all the planets is a great way to fix relative planet sizes in the minds of the student. Nothing beats setting up a project all on your own. The sense of achievement and accomplishment are great.

With the Solar System Model the students can do it all on their own. All that is needed is to get hold of a good diagram of the Solar System, and then replicate it in 3D. Any material can be used as long as it is sturdy enough to survive being worked with.

For the planets you can use ping pong balls, tennis balls, cricket balls, softball or even footballs. Then cover them in paint corresponding to the planet’s color. Get the Sun fixed in the center of the board and mark the orbits of the planets around it.

You can add as many details as you like to the model. The Asteroid belt between the Earth and Mars, or the moons of all the planets, don’t forget the rings of Saturn. Just have fun and enjoy the process.  If you are looking for more elementary science projects you may find some more here.