Well, I don't think it's really very likely that "The Fall of the House of Usher" was all an elaborate practical joke on the narrator, but it was a very entertaining theory. :) (I strongly suspect the guys who came up with it were testing the teacher's tolerance. She was entertained too, although perhaps it's not so much that the text suggests that interpretation as that it permits it, especially if -- I can't recall -- that story's one of the ones supposedly being told by asylum inmates.)