Quite good, despite inconsistent POV decisions
The first jarring thing is when we switch from Andrew's recordings to someone else's, but then a good way into the movie they just abandon the found footage conceit and show us things from an omnipotent POV. BUT, then they keep trying to return to having cameras justified even when it doesn't make sense (why would Matt's girlfriend keep recording when he runs out with nosebleed to find Andrew? That whole sequence is from her camera POV as though she never stopped recording even when in personal peril in the extreme. It made no sense especially given that they'd already shown us scenes where there was no camera to 'see' what was happening.
On the whole, though, a good variation on an overused theme with decent performances and characters we understand. Also one of the better movies relating the high school experience.