PG-13, 113 min.
This ain't your grandma's Beowulf. Beyond its vaunted 3-D effects, fine use of "performance capture" (which adds lifelike movement to animated characters), and sustained screen time for a naked Angelina Jolie (who plays the monster Grendel's mother), this Beowulf takes major liberties with the epic poem and won't likely make the cut for your students' Old English classes. (Although Jolie's nipple-less-but-otherwise-lifelike breasts apparently were non-titillating enough to help the flick make the PG-13 cut—go figure.)
But there's no question the latter elements make Beowulf a preferred way among teenagers to spend two hours (especially guys), who won't have any problem getting into the theater—so beware. Between the over-the-top, bloody violence, sexual banter, and plenty of near nudity (apart from Jolie's scenes), there are a few teachable moments, namely when Beowulf declares that a fledgling religion called Christianity has turned men into "weeping martyrs full of shame." But if you use such scenes with your group when the DVD releases next February, do so with caution—make doubly sure your kids know you're not endorsing the whole thing.