Everything you need to understand or teach The Berlin Stories by Christopher Isherwood.
William is the narrator of "...Mr. Norris" - events, characters and circumstances are described from his point of view. It could be argued that he is also something of a protagonist, in that his experiences are central to the narrative line - he plays an active role a number of key events (i.e., Mr. Norris' scheme to involve the Baron...
The Berlin Stories: The Last of Mr. Norris, Goodbye to Berlin Lesson Plans contain 88 pages of teaching material, including: