Substitute Creacher was a halloween inspired fable aimed at teaching children appropriate schoolroom behavior. I don't really know what to say about this story. I read it to my nephew, and while he was impressed with the pictures, for him the story didn't seem to be all that impressive. He just didn't get this story. Developmentally he's not yet at the stage of being able to extract a moral from a fable and then apply that moral to an existing situation or behavior. He's still very literal.
What's more, I'm not really sure how impactful this story is as a fable. The comeuppance that each of the misbehaving children got was so unlikely, I don't know how a kid could realistically come to a, "oh, I'd better not do that sort of thing" conclusion (e.g., a glue eater's fate is winding up with all kinds of junk stuck to him. Why didn't he just wind up feeling sick?). It was just kind of an odd book with a handful of decent pictures. Meh.