Fast Times at Ridgemont High (1982)

Cameron Crowe went undercover as a student at a San Diego high school and turned the year into a book, then this script, and that reporting is why the kids feel like real teenagers rather than movie ones. Amy Heckerling's directing debut juggles mall jobs, first sexual experiences and Sean Penn's stoner surfer Jeff Spicoli, whose running battle with history teacher Mr. Hand is pure comedy. It is franker about sex than most teen comedies, including an abortion storyline handled with more care than its reputation suggests, while some of the camera's leering at Phoebe Cates has aged badly. It entered the National Film Registry in 2005.