1. Fight Club (1999)
Despite the fact that Fight Club's most ardent fans are probably those in their mid- to late-teens, it is actually possible to avoid seeing this in high school. In fact, after my first time watching it (in the midst of my senior year), I had a pretty hard time finding someone to discuss it with. But once your failure to see it becomes known on a college campus, you might go one more hour without this apparent sin being rectified. So why is it so popular? The fact that it is arguably Brad Pitt's best role (and that he's shirtless and buff for a good deal of it) has a lot to do with it. Ed Norton also has a pretty big collegiate following. But it's probably that huge WTF? ending that makes watching it, often more than once, such a necessity.
2. Garden State (2004)
Who would've thought that Scrubs's most cheerful manboy, Dr. John Dorian, had so many inner demons? Certainly not most of Zach Braff's pre-established fans. The sheer surprise at his oh-so-artsy tribute to New Jersey might explain some of the interest it it, but really we all know that the soundtrack is what made this movie so popular. It almost single-handedly launched the career of The Shins and made "Such Great Heights" a new favorite song of teens and countless commercials alike.
3. Almost Famous (2000)
I was most surprised to discover that this was such a college must-see, but the more I think about it, the more it makes sense. First and foremost, it pays homage to '70s rock 'n roll, a genre rivaled perhaps only by the bro music of Jack Johnson and Co. as the most preferred of college students. Secondly, it laces this music into a sweet coming-of-age tale featuring a blend of wonderful under-the-radar actors and NBC's comedy line-up (including Rainn Wilson as a Rolling Stone editor. If you didn't notice it the first time, rewatch it! Trust me, seeing Dwight Schrute in a curly '70s fro and equally amusing outfit is so worth it). You really have to wonder why Kate Hudson doesn't make movies like this anymore...
4. Pulp Fiction (1994)
This one's kind of a no-brainer. It's got cult figure Samuel L. "Motherfucking Snakes" Jackson as the ultimate badass, paired with the quirky choice of John "Grease Lightening" Travolta in one crazy bloody (hot? tranny?) mess of a movie. The dialogue is offbeat, the sequences memorable, and structure as non-linear as you can get, making it the perfect companion to the equally offbeat, memorable (and regarding our recollections of some particularly inebriated nights, non-linear) college experience.
5. At Least Two "Classic" Will Ferrell Comedies
You're bound to get introduced to a few new comedians while at college, but it would seem that Will Ferrell is the most universal fail-safe. Which is why I think it's safe to say you'll have to watch not just one, but two (or, depending on the crowd, closer to twenty-two) of his movies. It's a bit unfair to call Wedding Crashers a Will Ferrell movie, considering he's barely in it, so I'd bet that those two choices are going to be the middle-aged, contemporary retelling of Animal House, Old School, and what is probably Ferrell's Citizen Kane, Anchorman: The Legend of Ron Burgundy. If you're looking for a little-seen toned-down Ferrell though (contrary to popular belief, it does exist), definitely check out Stranger Than Fiction, or Dick for all you history nerds out there (despite its X-rated title, it's a Watergate spoof, with Ferrell as Bob Woodward).