Earth revolves around the sun once a year and rotates on its axis once a day. The moon orbits Earth and is classified as Earth's satellite. The sun is the center of the solar system. Students are asked to choose the best model of the Earth and moon from options of using different fruits, with the correct choice being Earth represented by an orange and the moon by a cherry. The moon lacks an atmosphere so there is no wind, and its gravity causes tidal forces on Earth and different moon phases as it orbits.