Kathy transfers to Arnold's school and is treated very poorly because of her disability. When she becomes hall monitor, she rules with an iron fist and doles out demerits to everyone except Arnold. When Arnold feels the heat from his friends over getting away with everything, he tries to get Kathy to lighten up, but she refuses and gets tough with Arnold instead.

Mr. Drummond trades rooms with Willis while he is busy studying for exams. However, sharing a room with Arnold leads to discomfort for Mr. Drummond, while Arnold finds much humor at his expense.