Rock School (2005)

On stage, a budding guitar god — he's perhaps 12 — whips off the opening solo to ''Black Magic Woman'' as if he'd been sprung from the rib of Carlos Santana. Sound at all familiar? I've always thought that movies should be watched, and judged, independently of each other, yet I'd be lying if I didn't admit that Rock School, Don Argott's amusing and spirited documentary, would seem a heck of a lot niftier if its fire hadn't already been stolen by School of Rock. Whether or not that great 2003 Jack Black comedy was ''inspired'' by the Paul Green School of Rock Music (a wee bit of controversy has already swirled around the issue), the novelty of kids learning to play rock & roll in a structured setting, absorbing a ''devil chord'' as systematically as a Bach triad, no longer carries the same zing.

Green, a testy and demanding fellow who has run his school in Philadelphia since 1998, is a bigger control freak than Jack Black ever was; he's more like Dave Matthews played by Paul Giamatti. Most of Green's students are teenagers rather than grade-schoolers, and his most distinctive achievement is teaching them to play some of Frank Zappa's trippiest riffs. When they attend the annual Zappa festival in Germany, where they perform ''Inca Roads'' in concert with veteran Zappa sideman Napoleon Murphy Brock, it's funny and moving to see this eccentric nugget of boomer virtuosity played by a generation that has absolutely no idea how weird it was.