It's called The Surge. Here's a discription of it.

A trip to the woods for four outcast teens from Mar Vista High becomes a supernaturally empowering experience. They stumble upon a magical stone that changes their human personas into evil, mood-shifting teenagers.
Returning to school, they are able to channel this new found power to become popular and perform tasks of a mental and physical nature that previously eluded them and kept them on the fringe of the social scene. Hideous vengeance is about to be enacted against teachers and student adversaries in the final moments of this companion piece to DISTURBING BEHAVIOR.
Has anyone seen this? I'd like to know more about it.

Well I havn't seen the surge... but you just reminded me of Disturbing Behavior, damn that movie sucked... I had completely forgot it:)