If you’re anything like me, you probably heard about the premise and the title of Bad Teacher and immediately thought it was just a rip-off of Bad Santa. That would be a perfectly understandable reaction, but only for those who haven’t seen the film. In truth, this movie has several differences from the Billy Bob Thornton holiday film, first among them being that Bad Santa was far and away funnier and more quotable.

Don’t get me wrong, Bad Teacher does have its share of laugh-out-loud moments. It may not be nearly as crude as its Christmas counterpart, but hey, these are teachers in a middle school. As such, there’s a bit of humor in all the wholesome ways to swear and make sexual overtures (two words: dry humping). Even so, there are still some occasional crass moments from students, and watching the teachers vent when there aren’t any students around can be very funny.

However, what really sets this film apart from Bad Santa is that the latter film had an agenda. Our protagonist in that film was an entirely unlikable asshole who scammed sympathetic characters, the better to show just how important Christmas magic is to children by watching him wantonly destroy it. In Bad Teacher, the eponymous Elizabeth Halsey (Cameron Diaz) is scamming a bunch of parents and teachers, all of whom are practically begging to be duped. They may be well-meaning idiots, but they’re idiots all the same and therefore nearly impossible to relate to.

Fortunately, these characters are all being played with a sizable amount of comedic talent behind them. The cast includes John Michael Higgins as the principal and Thomas Lennon as an unfortunate educational bureaucrat, with Molly Shannon and Deirdre Lovejoy both making appearances as parents, just to name a few examples.

Lucy Punch deserves a special mention as Elizabeth’s rival, Amy Squirrel. She’s a very well-intentioned teacher who intends to get Elizabeth fired for all her many, MANY transgressions throughout the film. Yet the lazy, manipulative teacher with a filthy mouth and a drug problem gets through the movie without any repercussions whatsoever (aside from a dodgeball to the head, anyway) for her many criminal acts. In fact, it’s the hard-working, and chipper model teacher who suffers for her actions. And here’s the kicker: This is actually a satisfying ending!

The trick is that Elizabeth gets out of trouble in ways that are clever and often funny to watch, so our suspension of moral judgment is rewarded with humor and the satisfaction of following a smart protagonist. Secondly, Elizabeth develops in a positive way, growing as a character while Amy descends further into index-finger-looping-around-the-temple insanity. Thirdly, Amy only does one thing in her quest for justice that’s totally unethical and unquestionably illegal, and it’s that very thing that comes back to bite her in the end. Thus, the comeuppance is warranted.

I also feel that I should mention Justin Timberlake. With his past few movie roles and SNL appearances, Timberlake has already proven that he has a ton of acting talent, a great flair for comedy and a total lack of shame. All of these are put to great use here. Timberlake very effectively plays an attractive love interest for Elizabeth while also making it clear that he’s completely wrong for her. Really, he’s just another totally vapid and squeaky-clean loser, just like any of the other dupes that Elizabeth spends the whole movie taking advantage of.

In the entire movie, Jason Segel’s gym teacher may have been my favorite character. This is for the very simple reason that Russell Gettis is the sole person in this story who’s relatable. He’s the only character in the film who’s both reasonably intelligent and a decent human being, making him the straight man of the piece. As such, Russell is also a character who works to highlight just how nutty his coworkers are and to bring out the best in our protagonist.

Then there’s the matter of the students, who don’t play nearly as prominent a role as I might have liked. Maybe the casting director couldn’t find enough talented kids or maybe the filmmakers wanted to avoid looking like they were ripping off <em>School of Rock</em> as well, but only two of the students are even worth mentioning. One of them — an overachiever named Sasha (Kaitlyn Dever, a dead ringer for Miranda Cosgrove in School of Rock) — gets a development arc that goes absolutely nowhere despite her sizable amount of dialogue. The other one, a sensitive loser named Garrett Tiara (Matthew J. Evans), is the film’s only student who’s done right. Though he may not get much screen time, he does get an arc that ends in a heartfelt, hilarious and devilishly clever fashion.

Finally, there’s Diaz herself in the role of our main character. There’s no denying that Diaz perfectly looks the part: Gorgeous, but with something in her eyes to suggest so many years of hard drinking and drug abuse. Diaz is also very funny in a self-deprecating way, completely unafraid to make the character as unsympathetic as possible while also selling her development into slightly less of a bitch. Best and perhaps most importantly, she does a great job of playing manipulation. It’s really quite enjoyable to see this character tell a blatant lie or make some completely empty speech, simply because Elizabeth and Diaz are both really damn good at it. I’m not saying this is Oscar-worthy stuff, but the entire film depended on Diaz and she carries the film serviceably.

Bad Teacher is ultimately a nice waste of time. There were a lot of wasted opportunities here, with characters that went undeveloped and relevant satire gone completely untapped. What’s more, the narrative is almost entirely predictable and precious few of the characters are anywhere near relatable, but there are still a ton of funny and clever moments to be found here. All told, I’d say this is worth a rental or admission to a second- or third-run theater. Having said that, if humor is all that you ask from a comedy, this one is probably for you.