Creating a 3D model of the solar system is a staple of any grade school science program. A simple trip to a crafts store is all you'll need to get started on building an accurate 3D solar system.
Identify the foam balls with their planetary counterparts. The sun is the 6-inch ball; the 4-inch ball is Jupiter; the 3-inch ball is Saturn; the 2 1/2-inch ball is Uranus; the 2-inch ball is Neptune; the 1-inch ball is Mercury; 1 1/2-inch balls represent Venus and Earth; and 1 1/4-inch balls represent Mars and Pluto. The rings circle Saturn.
Paint the planets. Using the toothpick to hold the planets and the paintbrush to apply colour, paint the planets with their appropriate colours. Mercury is grey; Venus, light yellow; Earth, blue and green; Mars, red; Jupiter, bands of orange and white; Saturn, light yellow; Saturn's rings, light brown/red; Uranus, light blue; Neptune, light blue; and Pluto, light brown.
Cut the wooden skewers into lengths representing the distance from the sun. Mercury would be 2 1/2 inches from the sun; Venus, 4 inches; Earth, 5 inches; Mars, 6 inches; Jupiter, 7 inches; Saturn, 8 inches; Uranus, 10 inches; Neptune, 11 1/2 inches; and Pluto, 14 inches.
Glue one end of the cut skewers into their corresponding planets. Use toothpicks to hold Saturn's rings in place around the planet.
Glue the other end of the skewers into the sun around its centre in order of distance closet to the sun. Allow the glue to dry.
When painting planets with multiple colours, apply one colour first and allow the paint to dry before applying the second colour. After completing the 3D model of the solar system, you can place a hook into the top of the sun for hanging purposes or use a wooden skewer through the bottom of the sun to attach to a base. In recent years, Pluto has been declassified as a planet, so you may want to exclude it from the 3D solar system.
Have a parent or teacher on hand to supervise the creation of the solar system.