This movie isn't great by any metric, but it has a certain charm. The main characters have annoying qualities (bad jokes, charicaturized teen vanity, and for-the-love-of-god-just-tell-her-that-you-like-her-itis), but those qualities end up being turned into the very thing that causes the heroes' downfall, which was good, but it didn't feel like it was thought out as well as it should've been. It switches between two protagonists without really developing why it's doing so in a way that's awkward and more than a little jarring, and the ending (which I won't spoil) isn't particularly satisfying. That all said, the actors do a good job with what they have, and the villains are actually quite decent, with a motive that makes sense and interesting personalities that foil the heroes very well. It has some fun sequences, and featuring a Marianas Trench song is always a plus in my book.
Overall, it's not unlike higher-budget Goosebumps (fitting, given that it's based on an R.L. Stine novel and executive produced by the author himself). I'd recommend it if you have a 10-12 year old that's starting to have a budding appreciation for horror, or if you just want something fun that you can play in the background while doing something else.