This unit's purpose is to teach elementary students responsibility toward their pets by examining laws related to owners' responsibilities, medical care, and items which can be purchased for pets. The project, intended to cover 15 class days, provides teaching concepts and resources and presents each lesson in terms of a problem. Lessons include boarding a pet, allowing a pet to have babies, caring for pets, deciding upon legal ownership, and handling legal issues involving pet offenses. A mock trial, which concerns a pet's destruction of a person's property and the act's resultant altercations, is appended. Information concerning preparations for the trial, witnesses' statements, the major arguments of the plaintiff and the defendant, and the bailiff's and judge's roles are included. An outline for a classroom discussion about possible ways this case might have been decided is provided. A calendar, which can be used to plan the unit, is included. (JHP)