Create a model solar system for a school science display or for an individual art project for your child's room. Solar system mobiles can be used to teach children about the solar system and placement of planets. Children are visual learners, and allowing them to create a rendition of the solar system from the ground up is an excellent learning aid. Work closely with your child to answer any questions and to offer support of the construction.
Create the top of your solar system using the cardboard circle from a frozen pizza. The circle should measure 30 cm (one foot) across. Using your ruler, create a straight line from the top of the circle to the bottom and another line from side to side. The lines will cross in the centre of the cardboard; this will be the position of the sun.
Place the point of the compass in the centre of the cardboard, where the sun will be. Using the pencil of the compass draw nine different circles, each one expanding out a bit, to create the orbits of the other nine planets. Mercury, Venus, Earth and Mars orbit closely to the sun so you'll want to make those circles closer in toward the centre of the cardboard. Leave a 5 cm (two-inch) gap and draw the orbits for Jupiter, Saturn, Uranus, Neptune and Pluto. The gap signifies the asteroid belt that orbits between Mars and Jupiter.
Use the sharp point of the scissors to make one hole in the centre of the cardboard for the sun and one per each orbit circle; this is where the planets will attach to the cardboard. The holes should be big enough for your thread to fit through but small enough that a knot in the string could not pass through.
Draw your planets on your sugar paper. You can use various colours of paper to represent your planets or create the planets from one colour and use crayons or markers to create identifying marks for the individual planets. The sun will be the largest circle. Jupiter, Saturn, Uranus and Neptune will be medium-size circles; remember that Saturn has rings around the planet. Mercury, Venus, Earth and Mars need to be smaller circles and Pluto is the smallest (if you're including it: it's technically only a dwarf planet). Cut the shapes out.
Make a hole in each planet near an edge using the hole puncher. Tie a piece of string to each planet so that the planets hang about 20 cm (8 inches) from the top of the mobile. String the sun and each planet to the base by slipping the string through the hole and double-knotting it on the other side. If the hole is too big, then tape the top of the string to the other side of the cardboard to secure it.
Use the hole puncher to create four holes near the edge of the cardboard circle; the holes should be evenly spaced apart. Cut four pieces of string 20 cm (8 inches) long. Insert one string through each hole working from the "wrong" side of the cardboard to the solar system side. Double-knot the end of the string. Pull the four strings together on the "wrong" side of the cardboard and tie the ends together so that it creates a balanced effect for the planets. You will hang the solar system using the knot you just created.
Use polystyrene foam balls in place of construction paper for a 3D effect.
Use caution when making holes with the tip of scissors.