Somehow Homer comes to teach an adult education class on how to have a successful marriage. Even stranger, he turns out to be pretty good at it, dispensing homespun advice that his students find useful. He also dispenses quite a bit of personal information and gossip about his marriage to Marge, which causes his better half to go half-crazy. Homer apologizes but can't seem to stop airing their dirty laundry in class. Marge kicks Homer out and he begins sleeping in Bart's treehouse. Under these conditions, Homer begins to degenerate. After listening to her husband apologize profusely, Marge realizes that Homer needs her more than anyone else in the world and accepts him back.
