Ok hear me out:
Fatal Frame, but for kids!
I guess I would do something like that where a couple of kids are at their grandparents or something for the summer and they find out secrets of their town and how ghosts wander but only they can see them. They find out tidbits of what their lives were when they were alive and how the town used to be. We throw in Scooby Doo, Casper and Ghostbusters references for good measure.
I've got other good ideas but I'm actually trying to write those into stories.