Cameron Diaz has been in a lot of films I wouldn't consider worthwhile, to the point where I’m not really a fan anymore (try watching "The Other Woman" and then try to find something good about it – you won’t). Here, though, she finds a genuinely funny part and commits fully. Elizabeth Halsey (Cameron Diaz) is a teacher who plans to leave her middle school after a year to marry Mark (Nat Faxon). After being dumped, she realizes that the only way to land a wealthy man is through large breasts. She goes back to teaching at the middle school, determined to get the ten thousand dollars needed for breast augmentation and another rich guy in the form of substitute teacher Scott (Justin Timberlake), who’s interested in veteran teacher Amy (a very funny Lucy Punch). Elizabeth also has to fend off the advances of the nice gym teacher Russell (Jason Segel), and starts a campaign of dishonesty to achieve her goals. The script occasionally goes too far, but thankfully Elizabeth doesn't soften or learn any lessons throughout the story. She’s not particularly enjoyable to be around, treating her coworkers and students with equal contempt, but you find yourself sticking with it just to see what she’ll do next. Diaz wasn't my first thought for this role (Melissa McCarthy would have been perfect), but I was surprised by how funny she was in a part that isn't glamorous. The supporting cast is uneven; I didn't feel much connection between Diaz and either Segel or Timberlake, but the best moments were watching Elizabeth clash with Amy. Lucy Punch delivers a flawless performance, and seeing Elizabeth deal with her is great. The student actors are also good; Elizabeth’s blunt honesty about their lives feels almost refreshing these days. Jake Kasdan directs confidently, eliciting laughs in nearly every scene. The screenplay drags in the middle. Once it's established that Elizabeth is an awful teacher, we sit through a lot of extra scenes that seem to repeatedly hammer the same point home (like the Christmas dinner at one student’s house). Overall, "Bad Teacher" was a pleasant surprise, and it’s disappointing that we didn’t get more Elizabeth Halsey because the ending could have easily led to a funny sequel. A short-lived television series based on this film appeared, but too many changes prevented it from succeeding. I give it three and a half out of five stars. The Unrated version includes some physical violence, strong language, sexual content, brief nudity for both men and women, mature situations, alcohol and tobacco use, and drug abuse.

Source on TMDB