In Grease, innocent Sandy breaks up with John Travolta after he tries to pressure her into sex. For some reason, she immediately regrets this rash decision and sets about remaking herself in the image of the slutty women he seems to prefer. The change includes taking up smoking, changing her mannerisms and even getting rid of her accent.

Is Sandy in love or the witness protection program?

It's not just women who are encouraged to erase their personalities, though. In American Pie, Chris Klein can't lose his virginity until he totally transforms himself from a douchey jock into a douche bag who wears sweaters. And of course, in Grease, John Travolta can't make his car fly until he undergoes a personality wipe that takes him from greaser to ... greaser in a sweater?

"Yeah she risked getting pregnant and took up a life threatening habit, but I'm wearing a f*****g sweater over here."

In The Breakfast Club, the mysterious, silent Allison gets a makeover that transforms her from standard "cute goth" to "hip and sexy," which in the 80s meant that all of her clothes look like they're made out of pillowcases.

"Huge improvement." - Guy who's not to be trusted around children.

Popular jock Andrew, who up until this point has regarded Allison as an unusually talkative piece of furniture, is immediately enamored, rewarding the former outcast by holding hands and kissing her. It's the beginning of what we're sure turned out to be a happy and long-lasting relationship.

None of these, however, is as brutal as the 1999 film She's All That, in which a popular student named Zach spends the film remaking the brooding, artistic classmate Laney to better fit the tastes of him and his friends. He gets her to wear contacts instead of glasses, has his sister cut most of her hair off, gets her to wear makeup and dresses her in heels and the exact same skimpy dress that his ex-girlfriend wore.

The message being that women are interchangeable.

Zach ultimately ends up winning Laney's love, making the message pretty clear: If you can't find a girl you like right away, you can pretty much just create one to suit you from scratch.

As seen in: The Breakfast Club, Ferris Bueller's Day Off, 10 Things I Hate About You

So you're a young woman attending a typical American movie high school, and you're unhappy. Maybe your problem is that you're too smart for your classmates, or too popular, or related to someone who's too popular (yes, those actually count as problems in the world of teen movies). Fortunately, the solution for female teen movie angst is both simple and close at hand. And that hand is wearing handcuffs. And a knuckle-duster.

Ladies, you are apparently all about this s**t.

Jeanie, Ferris' sister from Ferris Bueller's Day Off, has a life consisting of storming around angrily and complaining about her popular brother. That is, until a drug addict in a police station strikes up a friendly conversation by telling her she looks like a whore. Flattered, Jeanie soon starts making out with him, which luckily gives her a saliva-based personality transplant. Thanks to the magic of criminality, Jeanie transforms from uptight b***h to giggling, happy schoolgirl who is willing to protect her brother from the consequences of his truancy.

Like Jeanie, Kat from 10 Things I Hate About You cares enough about her future to actually attend school, but she takes things even further down the road to squaresville, unabashedly reading outside of school. This chick needs to seriously to loosen up, right? Fortunately, she finds lasting happiness with Patrick, a troublemaking student who early on in the film is shown attacking another boy with a drill for attempting to talk to him. But it's just that devil-may-care attitude that enable him to teach Kat to loosen up a little and to show her that getting embarrassingly drunk at a party isn't the end of the world, a code of ethics that teen movies and date rapists swear by.

Pro Tip: In real life, the guys lining up to walk your hammered ass home from the party won't look like 1999 Heath Ledger.

In The Breakfast Club, self-described "criminal" Bender continually acts up in front of the too-popular girl Claire (Molly Ringwald). He tears up library books, sets his shoe on fire, pulls a knife on another boy, goes into a screaming rage, punches himself and repeatedly attacks anything near him that is lying on a flat surface. In case that wasn't charming enough, he repeatedly insults Claire, attempts to molest her while hiding under her table, proposes ganging up with another male student and impregnating her and eventually reduces her to tears.

In other words, he's a charmer.

It doesn't matter that Bender doesn't seem like he'd be remotely fun to hang out with. He's a juvenile delinquent and therefore, the teen movie universe's Yoda when it comes to loosening up and enjoying life. Unfortunately, that leaves one of the all-time classic teen movies with a love story that plays out like a cult inductee being emotionally broken and then taken advantage of.

And on a related note...

As seen in: Sex Drive, Ferris Bueller's Day Off, License to Drive, The Karate Kid, The Goonies

So you're a character in a teen movie, and you want to have nonconsensual sex with many unconscious women, but you don't have a way to get there. No problem! Just steal a car, and it'll all turn out OK, even if you don't have a license. In fact, not having a license will just add more excitement to the whole gig, like the way open-heart surgery gets more exciting when nobody in the room has gone to medical school.

And we've all been drunk for days!

In Ferris Bueller's Day Off, Ferris persuades Cameron to steal his father's rare 1961 Ferrari, and they both must deal with the consequences of this serious action: the best day of their lives! Sure, Cameron does end up having to take responsibility for his actions. But only because of a freak accident that comes about because -- you guessed it -- two other best friends steal the car, roll up the miles on the odometer and have what appears to be the single most enjoyable joyride in the history of Ferraris. In sum, Ferris Bueller's Day Off plays like a PSA about car theft, where the message is, Everyone's doing it, and it's so fun that even if you get caught, it'll be worth it!

Ah, to be young enough to be tried as a minor again ...

Of course, Ferris is a driver's ed instructional video compared with License to Drive, in which Corey Haim doesn't let failing his driving exam stop him from stealing his grandfather's Cadillac to impress a young Heather Graham. This leads to a series of nearly fatal accidents -- their vehicle hydroplanes and careens down a steep hill, they get involved in a fun high-speed chase in pursuit of a drunk driver -- before the unthinkable occurs: The car ends up getting totally trashed!

Fortunately, Corey gains the admiration of his entire family when he uses his newly acquired badass driving skills to rush his pregnant mother to the hospital in reverse gear, almost killing several pedestrians when he drives on the sidewalk to avoid traffic. In the film's final scene, Corey's father forgives him before Heather Graham pulls up in a Volkswagen. Everything being resolved, Corey jumps into the driver's seat and speeds off happily as the credits roll. Wait -- he still doesn't have a f*****g license.

But hey, a license is just a piece of paper. That stops the police from throwing you in jail.

In fact, John Hughes' entire filmography seems intent on pushing the "driving without breaking the law is for squares" agenda. Weird Science, Sixteen Candles and Some Kind of Wonderful all feature young teen heroes casually mentioning that they don't have a license before hopping into their cars and driving away. According to these movies, any driver training is optional; you just kind of pick it up after you find yourself on a highway going 80 mph with your screaming friends in the back seat. Then you just cruise your way into a series of zany events in which nobody ever turns out arrested or dead.

In The Goonies that character is Troy, whom we meet as he's wearing his letterman's jacket while driving down a winding mountain road. When he happens upon Brand (Josh Brolin), who for reasons not worth recounting here is riding a children's bike, Troy proceeds to grab Brand and drag him from the side of his car at dangerous speeds before throwing him off a cliff while yelling, "So long, sucker!"

Really, he had it coming.

The only thing that could have made Troy a more psychotic a*****e is if he was played by Billy Zabka, who played the same bordering-on-psychotic jock in all of his movies. In The Karate Kid, he pushes a scrawny kid off his bike and down a steep ravine from the back of a motorcycle and orchestrates a five-on-one beating that ends when the one non-psychopath of the group points out that Daniel can no longer stand up. Wait, no, Johnny yells him down and goes in for what appears to be the literal kill, before Miyagi rescues his 16-year-old friend.

But it's not just Johnny. At the film's climactic karate tournament, Johnny's friends are worked into a murderous frenzy, with fellow athletes yelling things like "Destroy him!" and "Get him a body bag!" At least by this point Johnny is showing some reluctance, although that might just be because following their advice would involve murdering someone in front of thousands of eyewitnesses.

Is that really karate?

Revenge of the Nerds takes this a step further, when Ogre, one of the film's many semiretarded and thuggish jocks, is shown holding a man from his ankles from the roof of a two-story building and then letting him go. His victim plunges head-first and screaming toward the ground before falling eerily silent. Later, presumably after college security has covered up that murder, Ogre tosses another man head-first through a plate-glass window. He apparently faces no punishment, and the acts are never referenced again, as if murder-by-jock is an event so common that everyone just treats it as something inevitable, like jaywalking.

It was probably just a drama student or something.

As seen in: Pretty in Pink, Some Kind of Wonderful, The Karate Kid, She's All That

Conflict between rich and poor has long been a popular source of high school drama. Usually, in teen movies, it plays out the same way: The poor boy or girl falls in love with a rich girl or boy, there's some conflict, both teens learn an important lesson about prejudice, and everyone ends up happily making out next to their cars. It's a great life lesson! That is, until you start looking more closely at these movies' definition of "poor."

For reference, here's a traditionally filthy poor person.

In Pretty in Pink, Andie (Molly Ringwald) is the token poor girl whose father is chronically underemployed and whose impoverishment forces her to make her own clothes for school, where she is relentlessly bullied. When a boy takes her out on a date, Andie is too embarrassed to let him take her home, because she lives in a falling-apart trailer with plastic sheeting instead of windows. And the rich kids all have their own sports cars, while of course Andie has to take the bus to school because she's so poor, and-
Oh, wait. Actually, this is a shot of Andie's home from the film's opening scenes:

What a nauseating s**t-sty.

It's a comfortable, clean, two-story place. The pink car out front is Andie's; her father has his own. It's only when you look more closely at the picture that the horrible truth is revealed: The pink car has a dent in it. Obviously this family is hovering dangerously on the verge of starvation.

The reason the movie can get away with portraying Andie's situation as poverty? All the other kids are rich. Filthy, filthy rich. Andie's boyfriend drives a BMW and takes her to a country club. Their parents are always away in Europe, allowing them to have constant house parties with large amounts of good-looking people dressed in pastels. Andie cannot possibly compete, because after all, her father is shown in one scene sitting outside drinking beer.

What is that, a terrycloth robe? Eyurgh.

The same story pops up in Some Kind of Wonderful. Two "poor" friends fall out when one of them, Keith, falls in love with a fellow poor girl who has sold out by hanging around with the rich crowd. The evidence for Keith's poverty? He actually has to work after school to contribute to his own college fund. His friend Watts is similarly poor because she drives a beat-up car at 16, an age when any respectable American should already have a Rolls-Royce polished to a shine by a team of servants. Similarly, in The Karate Kid, Daniel feels rejected by his peers because he does not fit in at their country club dances. His fellow scrappy underdog, Mr. Miyagi, occupies a similarly low-status position as a handyman and lives in a place like this:

Unfortunately, only those with fewer than five classic cars qualify for food stamps.

It didn't die out in the 80s, either. She's All That features another outcast kid with a working single parent, Laney, whom other kids bully by saying things like: "Isn't your dad my pool man?" Laney's house:

The message is clear: If you live in a home that has fewer than 10 bathrooms, you'd better not even bother attending high school and skip straight to screwing hobos for canned goods, because you are clearly too poor for anyone to love you.

For more terrible movie messages, check out 6 Movies With Uplifting Messages (That Can Kill You). Or get your training on with montages, in The '80s Movie Montage Hall of Fame.

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And to further expand your noggin, check out Cracked's De-Textbook: The Stuff You Didn't Know About the Stuff You Thought You Knew.