Classroom solar system displays can be purchased on Amazon.com, Brookstone and the Modern Teaching Aids website, as of 2015. Each one greatly varies from the other in size, construction and design.
On Amazon.com, Learning Resources sells an inflatable Solar System. The set comes with a foot pump for inflating the various planets, as well as hooks to hang them. These planets are proportionally sized to give a sense of the size differences between the planets. However, the lack of a frame means teachers must use their best judgment when hanging these planets to adequately convey distance. Because of its soft construction, this Solar System set is appropriate for children as young as 6 years old.
Educational Science sells a motorized solar system display on the Brookstone website. This set comes with each planet attached to a central tower through a metal rod. Because it is motorized, the planets revolve continuously around the sun, positioned at the center. These planets are not appropriate for removal from the set and, due to small parts, can be a choking hazard for those under the age of 8.
Modern Teaching Aids sells a solar system model that also revolves around a central tower, with each planet connected by metal rods. It includes a CD with software that educates students about the solar system and the differences between the planets.