This is a teenage scary story flick with outsiders vs. bad boys vs. evil things unleashed by a mysterious girl who died many years ago. Don't expect any gore or blood - there is none. The story is good though and the acting is decent when it doesn't get too hysterical. The movie's pace and runtime are also good.
Guillermo del Toro has been involved with the screenplay, but I'm unsure if he did other than that. The monsters are CGI, so don't expect it to look like a Del Toro movie. It looks more like an André Øvredal movie, not that that's a bad thing.
All in all it's fine entertainment without unleashing it's full potential. If they had explored the story further and added gore, blood and torture it would have been more interesting, but probably they would have found it a bit difficult to hit the PG-13 rating then.
Bonus info: there are no extra scenes after the end credits, so don't wait for that.