This is the Whateley Academy Universe, a shared universe with over a dozen authors and more than a hundred stories.

As it states in the site WIKI, "Lions, Tigers, and Bears... oh, wrong story there. Those things wouldn't go near Whateley Academy if they were wise. Whateley is a Prep School for different teens. VERY different ones. Where else could a kid go to a school that has a resident demon living in the furnace? Or meet magic users, mutants of every imaginable kind, get trained in how to handle some rather odd abilities, and worry about flunking Freshman English? Come visit Whateley Academy, nestled in the lovely hills of New Hampshire. Just down the road from a town named Dunwich... (Mythos jokes purely intentional)."