The Crossroads is a pretty good ghost story aimed at kids in maybe 5th-7th grade. It was creepy, there was some violence, and there were kids in peril. All of this was enough to make kids in this age range appropriately freaked out, but not enough to be really and truly terrifying to them.
While the ghost story does take center stage in this book, it's also a story about Zack having to come to terms with the verbal and emotional abuse he suffered at the hands of his now deceased mother. He learns to lean on himself, to find value in himself, and he learns to trust in the bond that he's formed with his new step-mother. All of this is well done, and does not get in the way of or overshadow the ghost story.
As for the ghost story, it was good, but the majority of the ghosts in the story died in the 1950s. There is a lot of 1950s terminology and culture that goes on in the story, and I do wonder if that might not make too much sense to younger readers. I guess kids could understand the slang and the culture from context, but in some places it did come off as a little bit corny or dated.
Overall, though, I think it's a good story for those kids who like their books to lean a little dark. This one does have a dark streak, but it's the light that triumphs in the end.