Comedies can usually at least pacify their ineptitude with genuine affection and charm, uninviting hostility because of a degree of good will and sincerity. Then there are comedies like Bad Teacher, not so much vile as punk-ass, rolling its sleeves up to get dirty - only in the most puerile, absent-minded, and below-the-belt manner. There's hardly a scene or line that doesn't either puzzle or disgust in its carelessness. Lacking the gall to be provocative (much less any broader perspective to be remotely engaging), the film insults intelligence more than anything - and in fact, makes absolutely no sense.
Even on a basic narrative level, there's little operational rationality. Mid-30's Elizabeth Halsey (Cameron Diaz) seeks one thing - a sugar-daddy who can cover her materialistic, high-maintenance needs. She's also inexplicably a middle-school teacher, indifferent and apathetic to any and every one of her students. The film neglects to explain why Elizabeth got into education (much less why she's now so disillusioned), and it's an unforgivable omission, since she would have presumably been teaching for many years prior, allowing numerous opportunities to be outed by her ridiculous behavior. Furthermore, the film begins at the end of a school year, with Elizabeth leaving the very school she will eventually return to. So - let's try and follow the faulty logic. The remainder of the film will primarily be about her lying, stealing, and conning money in order to get a tit job so she can bag noob teach Scott Delacorte (Justin Timberlake), who apparently comes from wealth and could satisfy her expensive tastes (she thinks she needs bigger tits because his previous girlfriend had them, which is explained in merely a brief photo on his phone), while fending off straight-arrow shrew Amy Squirrel (Lucy Punch) from outing her fraudulence. What isn't explained is how Elizabeth's pedagogical traits (such as screening films instead of having lesson plans) went unnoticed in the previous year, nor how she would be utterly clueless that her students both needed to pass a year-end exam AND that the highest scoring class earned the teacher a lucrative bonus. Seems like someone with her priorities would have caught onto that. Moreover, why is she obsessed with Delacorte, a sexually incompetent buffoon (he prefers dry-humping over actual fucking), when she could roam the country clubs or high-end nightclubs to rope in a true hotboy, not some millionaire who's inexplicably a grade school teacher? Such questions remain unanswered, meaning even on the lowest common denominator, Bad Teacher doesn't work. If only that were the worst of its problems.
The humor. Where is it? What's the joke? Ask this question as the film begins and try to solve it by the end - it's an arduous task given the confluence of contradictory tones and vibes, ranging from scatological (a teacher takes an exploding shit) to situational (faculty meeting gags) to behavioral (men gawk as Diaz sprays herself with a hose). All trite, horribly unfunny stuff, but this is relatively innocuous, without offense. Where Bad Teacher really screws up is with the Diaz character; she smokes a bowl in her car, takes shots of Jack at her desk, embezzles money, and eventually even manages to steal a copy of the state-wide exam (roofying the helpless schlep in charge while posing as a reporter, natch). These actions range from contextually meaningless (the drinking and drug use) to off-the-rails tasteless (she even blackmails the guy to keep him quiet). How about some satire here? None at all? Why make a comedy about an egregiously careless teacher and not tailor it to address educational woes (and, at this point, crisis)? Weed and blackmail gags are the best scribes Lee Eisenberg and Gene Stupnitsky could muster apparently and director Jake Kasdan (Orange County, Walk Hard) remains in pretend mode, feigning scandal and shock-value, neglecting to engage the material with even the slightest proclivity for social consciousness. A late joke in the film sums up Bad Teacher's sour totality; having been framed for drug use, Amy is assigned to a new location, the worst in the district: Malcolm X High School. I'd give Bad Teacher an F, but it doesn't deserve even that shallow gesture.