Jocks, cheerleaders, nerds, goths and stoners - the American teen movie is peopled with types and tribes yet manages to speak interestingly about hopes and dreams that do not have just to do with skipping detention or going to the prom. In her new book, Roz Kaveney charts the development of the teen movie from a marketing category to a full-blown genre obsessed with smart answers to its own past. Starting with the groundbreaking John Hughes movies of the 1980s, and with Lehman and Waters' sardonic comedy ''Heathers'', Kaveney discusses the evolution of themes like the Mean Girl and the loss of virginity. She examines the metamorphosis of Jane Austen's novel ''Emma'' into the Beverly Hills comedy ''Clueless'' and the way the ''American Pie'' trilogy has subverted the gross-out sex comedy into a lesson in sexual manners. She looks at the link between these films and some of the most innovative teen television of the last two decades, including ''Popular'', ''Buffy the Vampire Slayer'' and the teen detective show ''Veronica Mars''. In the process, she demonstrates, with characteristic wit and intelligence, how teen films and TV series deal with the tragic and comic undersides of the American dream.