BAY CITY, MI—According to sources at Bay City Middle School, all of 51-year-old math teacher Lance Stonitch's in-class examples express numbers in quantities of Moon Pies, the snack item consisting of marshmallow fluff packed between round graham crackers and coated with chocolate, vanilla, or banana icing. "Let's say Jimmy and Janie eat 40 Moon Pies in two weeks," Stonitch said Monday. "Their friends John and Joe are coming to visit for two days, and John and Joe eat Moon Pies twice as fast as Jimmy and Janie. How many Moon Pies does Jimmy need to buy the week of the visit, to have enough Moon Pies for everyone?" While most of Stonitch's students have no idea what a Moon Pie is, eighth-grader Trace Crutchfield said, "Whenever Mr. Stonitch says 'Moon Pies,' we just think of that as a generic unit."