Barely any adults in the entire movie (spoiler)
Not a single teacher, not a single parent, not a single police officer.
Teenagers in the libraries and gym classes without any adult supervision. Students killed in the school, cars blown up in the parking lost, and still classes held the next day.
Only at the very end at the dance do we see any adults or police, and even then despite an explosion the adults decide to head back in to the dance.
You REALLY have to suspend your disbelief while watching this movie.
There's a message here though, even as early as 1976, about bullying in schools. There's no way such a movie could ever be made today as no company would choose to market it.
Overall about a 7/10 and the effects weren't back for the mid 70's.