I've read reviews that apparently you have to have been a student in a very strict, British school in the 1960's to understand this. Maybe that's true, if so, then this movie is outdated.
*************SPOILER ALERT**************************************** The ending makes about as much sense as all the kids who're anti-government and anti-corporation without having any better solution that doesn't torch society to a Mad Max type cinder.
Yeah, the main characters could leave, but they don't. The reasons they go about this don't make sense. There isn't enough character development to explain why. What shooting up a bunch of innocent people is supposed to mean is never explained or even hinted at. It is mentioned that war is the final creative expression, quite possibly the only revelation that any characters of this movie have, and it makes no sense.
The characters who go on a murder spree aren't fighting the institution, they're just killing people. I thought they might've used all the explosives to blow up the place or at least the sanctuary at the end, that would've made greater symbolic sense, but they didn't.
tl;dr - This movie is an adolescent's daydream of fighting against authority that plagues them, though in reality they need. It has no moral, symbolic truth, or meaning to it; this movie simply plays out the fantasy of killing teachers and people in "power" that annoy you.
If you think a murder rampage/ school shooting similar to columbine or virginia tech is a rational and sensible way to deal with teachers and institutions you don't like, then I guess you'll love this movie. If you're like me and you're working towards making a life for yourself instead of just blindly (very blindly in this movie) rebelling against "the man", this movie is juvenile and boring.
You can also tell in parts that funding was lacking, and the story seemed to have a touch of attention deficit disorder.
All in all, this seems like a very rough draft of what could've been an okay movie, but no effort is put into the dialogue, character development, or moral so it's just... poorly done.
If... only I could get my two hours back.