The writing, for me, in this one, is about the interaction between the characters. I am torn between wanting something evil / supernatural, like the group from IT trying to defeat Pennywise, and the group from Stand By Me, just out to do something real, but formative. 

I do like the notion of something going down at the carnival / fall fair. It's usually only in town for a weekend, which puts a cap on how long the adventure can go on... I also love the idea of a haunted house, or doing something as a team, like a soap-box derby, or something that happens at a destination, like a state park, or a summer camp.