Engrossing and often gross stories about being a sub/teacher's assistant for mentally challenged children. Dave Roche is not a perfect person, but he's clearly got guts to do this job. The situations he finds himself in - whether it's helping a kid in the bathroom or working with them on basic tasks that are beyond their capabilities - are hilarious and heartbreaking, and his low-key-but-seldom-absent sense of humor makes even the difficult-to-read sections within On Subbing a joy.