Prior to class, teachers had discussed the solar system bodies with the students and the students and drawn cards of each planet plus a comet and asteroid. Inside, the scale models of the planets were introduced, using a scale that made Earth the size of a kumquat. Outside, the students held their planet cards and were placed on the playground to showing the relative distance between planets. A third demonstration was to use pre-cut lengths of string to represent the distance from the sun to the inner planets, with students holding on to the strings and revolving about the sun.