Since there are only nine planets and most classes have 20 or more students, it may be necessary to work in cooperative groupings. An alternative is to have everyone construct a planet, thus having two or three versions of each planet. This detail would depend on the teacher’s preference. The important factor is that the creations come out to the correct size so that they are all in scale to each other.
The four gas giants (Jupiter, Saturn, Uranus, and Neptune) are created from the balloons with papier-mache, and then painted the appropriate colors. For anyone not familiar with the papier-mache process, there are two approaches worth considering. There is a product available from art supply houses called, “Art Paste” that is ideal for the novice as well as the professional. It is just a matter of adding water and waiting an hour for it to cure. Another viable product is standard wallpaper paste. After selecting a paste, tear the newspaper into 2 inch strips and cover the balloons with at least three solid layers of the paste-soaked newspaper strips. Let dry at least one day and then paint to match the planets.
The rings of Saturn can be created from a sheet of cardboard that is 78 centimeters wide (the size necessary for this scale to match the 274, 000 kilometer diameter). This will give the class the opportunity to work with geometry. If a large-size compass cannot be be obtained, then it is just a matter of using two pencils attached to opposite ends of a string 39 centimeters long. One pencil is the pivot and the other draws the diameter. Each smaller ring can be done by exchanging the outside pencil for a colored marker and shortening the string. Cut out the cardboard with a razor knife and continue the colored rings on the other side.
Attaching the cardboard ring to the papier-mache balloon is a little tricky. Take the 24 inch steel rod and pass it through the outside of the ring via one of the channels of the corrugated cardboard. Place the Saturn model inside the cardboard ring and continue passing the rod until the rod protrudes through the sides of Saturn and can slide into another channel on the opposite side of Saturn. Refer to
Illustration A
below for a clearer idea of how this is to be done.