Vinny Garrison is the technology teacher and racing commissioner at A. MacArthur Barr Middle School, in Nanuet, NY. Over the course of seven weeks, each eighth grader will shape a footlong wood block into a car and make a set of wheels on a MakerBot Replicator Desktop 3D Printer. Students eager to challenge the all-time record craft wheels weighing as little as eight-tenths of a gram. (Stock wheels can weigh as much as five grams each.) Others create elaborate patterns worthy of a custom rim shop while learning engineering principles.