Horrible Bosses, is one of those "Ronseal" films (in that it does exactly what it says on the tin) that should just fall into place as a relatively decent piece of throwaway entertainment. But whilst Horrible Bosses is a prime example of how not to get it right, Bad Teacher, although far from perfect, manages it somewhat better.
Cameron Diaz plays Elizabeth Halsey, the titular teacher who is forced to return to her job at a middle school after being dumped by her wealthy fiancé. She soon sets her sights on supply teacher Scott Delacorte (Justin Timberlake) as well as doing anything she can get away with to save money for the breast enhancement surgery she is longing for.
If you're looking for a moralistic tale, Bad Teacher isn't it. This is not a film where everyone who deserves it gets their comeuppance (although some do), nor is it a film that pulls any punches in terms of taste. It probably gets away with this about as often as it goes too far, resulting in a patchy mix that makes you laugh one minute and cringe the next.
Diaz seems to ease into the role as the film wears on, starting off somewhat unconvincingly but providing some genuine laughs once she hits her stride. Timberlake is fine in an unchallenging role, and Jason Segel as P.E. teacher Russell Gettis is likeable enough whilst providing a few entertaining moments throughout. Arguably the strongest performance here comes from Lucy Punch as painfully chirpy and enthusiastic teacher Amy Squirrel, who provides a terrific nemesis for Diaz's Elizabeth.
The film doesn't concern itself with much of a plot, instead moving relatively disparately from one set of circumstances to the next. This allows for some humorous scenarios and a handful of genuinely funny scenes in isolation, but means the film as a whole feels lacking in structure. Bad Teacher ultimately ends up as a hit-and-miss piece of bubblegum cinema that's enjoyable enough but never attempts to deliver anything memorable or of substance. Which is probably exactly what the filmmaker's were aiming for.