Viewer beware...you're in for a...actually, no. It might have been slightly scary for kids, but for the ones who grew up with Goosebumps (the books, the TV show, etc.) it seemed like a nice nostalgia trip. I'll try to keep this spoiler-free.
Two boys named, Zach and Champ, break into the house of R.L. Stine (Played by Jack Black and obviously the real R.L. Stine isn't exactly like this one...by the way keep your eyes open for his cameo) and accidentally open up the manuscripts for the Goosebumps books. Once Slappy the Dummy ("Night of the Living Dummy") is released, he gathers up all of the manuscripts and releases all of the monsters that Stine created so that they can wreak havoc all over the town. Now it is up to Zach, Champ, R.L. Stine, and his daughter, Hannah, to stop all of the monsters from destroying everything and everyone.
One thing that I absolutely loved from this movie is that most of the Goosebumps monsters are real actors in make-up and practical effects. The others are computer animated and even though you obviously tell which ones are CGI, it surprisingly didn't bother me that much. Though if I had to pick at least one flaw for the CGI it would be the Werewolf of Fever Swamp. If it were up close to the main characters, they could've at least used a wolf suit. Though with a budget of $59 million, I can see why they would resort to CGI, but other that, I was okay with what I have seen visually.
Another thing I really liked from this movie was the antagonist, Slappy the Dummy. Yes, he looks like Jack Black and yes, he was voiced by him. Before I viewed this film, I had doubts about this character. Originally, I wanted the dummy to look like how he was portrayed in the TV show or at the very least, the illustration on the original book cover. Thankfully, I was surprised by the performance and he did make me laugh. Though I still wonder how it would've been if he were voiced by either Jeff Dunham, Tom Kenny, or maybe even Frank Welker. Still it is what it is, and I wasn't disappointed.
The acting was decent, the music (by Danny Elfman) was nice, the plot is like a mix of Jumanji with The Cabin in the Woods for kids, and even though that alone sounds a bit flawed, I still enjoyed it. Would I want to see it again? Yes, but only when it comes out on Blu-Ray. All in all, if you grew up with and/or are a recent fan of Goosebumps, I would recommend it. Definitely around Halloween.