What is it about the sensual onstage twirling in 'Dirty Dancing'? What is it about Ferris Bueller doing the twist, with all of Chicago at his feet? Somehow your heart is pushed to bursting with vicarious triumph, despite the fact your own life will never feature such a scene of utter glory. That's what 'Bandslam' is like: rife with spirit-lifting scenes of teens singing their hearts out. And it feels just that good, in a quirky-smart way. This is a solid, smart film from writer-director Todd Graff. As the recent death of John Hughes reminds us of well-wrought teen movies, we might take consolation in the fact that such films continue to emerge, 'Bandslam' among them. It's an unabashedly sweet, zeitgeist-capturing movie that nerdy teens will be happy to grow up with and parents will be pleased to tag along to. Will Burton (Gaelan Connell) is a high-schooler who has recently moved from Cincinnati with his single mom (Lisa Kudrow). Maybe you've met this sort of boy: nervy and witty, introverted, unruly hair, impeccable taste in music, heart of gold. Such youths exist, and Will is their endearing, pitch-perfect embodiment. Will finds himself, after several quick twists of fate, -- collaborating on a class project with the bookaholic Sa5m (Vanessa Hudgens); no, we never learn whence the '5,' though we do know it's silent. Meanwhile, bombshell upperclassman Charlotte (Aly Michalka) takes Will under her wing. And Will whips Charlotte's band into shape for the upcoming Bandslam competition. Meanwhile, Will's romance-tinged friendship with Sa5m progresses with halting awkwardness and tender kinship. In one of the film's best sequences, the two sneak into the basement of the now-defunct punk venue CBGB, where Will spots an old Patti Smith poster and gasps in awe, 'Do you know how many times she must have spit on this floor?' As the film moves toward its inevitable heart-swelling musical conclusion at Bandslam, the plot cycles through its moments of undeniable fuzziness. But the script's earnest intelligence and the actors' charm (Connell, Hudgens and Kudrow are especially fun to watch) make this film an entertaining ode to teen-age joie de vivre. 'Bandslam' PG, 111 minutes Contains thematic elements, mild language and erudition-testing music references. 