Vice Versa (1988)

On returning from a buying trip abroad for the department store in which he works, Marshall finds he is in possession of a strange ornamental skull. Marshall is divorced and is looking after his son Charlie for a few days. The skull has special powers, and when Marshall and Charlie simultaneously wish they were each others age, father and son exchange bodies. Now Charlie has to go to work, and Marshall to school. Charlie also has to deal with Marshall's girlfriend. If that weren't enough a pair of smugglers are in pursuit of the skull.