Matthew arrives at Benjamin Harrison as a sub, inexperienced and unaware of what he's in for. Fed up with a lack of chalk and erasers, Sara keeps pressing for her transfer to another school -- one that's willing to pay for school supplies. Harry tries to help a failing gang leader, Julio, whom he wants to see get into college, but Jack's refusal to change Julio's history grade -- and Julio's not wanting it to be changed -- stand between them. Joe fights tooth and nail to prevent Benjamin Harrison's day care center from being shut down when the conservative school board decides that it glamorizes -- and encourages -- teen pregnancy. Matthew tries to teach, but the students just laugh at him and walk out of his classes... even after he follows Gus' advice on how to get them to stay. Sara demands Joe sign her transfer after a student swipes her copy of ""David Copperfield"" and refuses to return it. Like Sara, Matthew threatens to quit himself when the students turn him into an impromptu da

Jack has a physical for his wife's insurance policy, and is told he's in poor health. Harry unloads a troublemaker, Johnny, in Sara's class, because none of the other English teachers want him. Johnny walks out, and Sara tells him to never come back. Joe finds a way to get rid of Mr. Kaczmarek -- if his students don't pass a test Joe plans to personally give them, so long. Matthew follows Mary Caitlin, and discovers a secret she was trying to keep from the rest of the faculty -- she's participating in a church-sponsored program for runaway youths. Charlie has it out with Harry because he's stuck working in the rubber room pending an investigation. Mary Caitlin tries to no avail to help out one of the runaways, Sandy, who's got severe issues concerning her parents. Johnny begs Harry to give him another chance in Sara's class -- at least she was honest enough to say she doesn't like him. Mary Caitlin is angry to find out Matthew followed her, and confesses that she hasn't spoken to her m