Many of the other reviews on this site have rehashed the plot(s) and the fact that it introduced an amazing array of acting talent to the world. What I think is most impressive however, is the honesty and poignancy this film delivers while being hysterically funny. The relationship between Brad and his sister is incredibly touching. The characters are real, three-dimensional people (yes even Spicoli; I knew someone almost exactly like him in school and I'll bet you did too). It is beautifully written, directed, and acted. It is also one of the most quote-worthy films this side of Tarantino ("All I need are some tasty waves, a cool buzz, and I'm fine").
On a final note, I disagree with the Amazon reviewer's assessment that Cameron Crowe is an overrated director. "Say Anything" is probably the best teen movie made since this one, and "Almost Famous" is a stone cold masterpiece, IMHO.
Today's kids won't have a clue what's going on when the pop quiz gets handed out and everybody sniffs the paper. MMmmm... ditto paper......
I've heard that the Mark Ratner character was based on the guy that later went on to write Windows For Dummies. I hope that's true; it would be nice for the nerds to come out on top in the end!
If you're over 30 and you haven't seen this movie, go buy it right now. You'll be happy you did.
The case for the movie is easy to make: It is written by Cameron Crowe, who wrote Jerry Maguire, Say Anything, and Almost Famous. It is beautifully filmed and directed. (Director is Amy Heckerling, who apart from being awefully cute has made such wonderful movies as Clueless.) It is funny and real. And it has a magnificent cast of young actors who where unknowns then.
The surfer/stoner is famously played by Sean Penn in one of his first roles, and he is awesome. Jennifer Jason Leigh is perfect as the young innocent fifteen-year-old. (Amazingly she was about 20 when she played it, but you'd never know it.)
And Phoebe Cates... As Amy Heckerling says in a featurette: The boys just loves Phoebe... the rental cassettes always track a lot around the place where she takes off her top, they've been freeze-framed so much..." Which is as good a reason as any to get the DVD version, they slow-mo and freeze-frame a lot better... But seriously, Phoebe is a wonderful actress who has been woefully underused by Hollywood. And she is also just stunningly cute to boot. Even if this film had nothing else going for it, get it for her. (She is also excellent in the later film Princess Caraboo, and she is buck nude in the light "Paradise", which I hope they will put on DVD soon.)