The Gym Teacher from the Black Lagoon (2009)

This animated film centers around a boy named Hubie, the star of the many "Black Lagoon" books by Mike Thaler and Jared Lee. Hubie’s class is getting a new gym teacher, nicknamed “Coach Kong” for his barbaric treatment of the students. Hubie is sure he's doomed...but when he actually gets to gym class, will things be as he expected?