Elizabeth Halsey (Cameron Diaz) is a Chicago area teacher who curses at her students, consumes lots of alcohol and drugs, and only shows movies while she sleeps through class. She plans to quit teaching and marry her wealthy fiance, but when he dumps her, she must resume her job as a teacher. She tries to win over substitute teacher Scott Delacorte (Justin Timberlake), who is also wealthy. Amy Squirrel (Lucy Punch), a dedicated teacher and colleague of Elizabeth's, also pursues Scott, while the school's gym teacher Russell Gettis (Jason Segel) makes advances on Elizabeth, which she rejects.
Elizabeth plans to get plastic surgery to enhance her breasts, but cannot afford the $10,000 procedure. To make matters worse, Scott admits that he has a crush on Amy, only viewing Elizabeth as a friend. Elizabeth attempts to raise money for the surgery by participating in her 7th grade class car wash in provocative clothing and by manipulating parents to give her money for more school supplies and tutoring, but her efforts are not enough.
