Slaughter-house five

I am in english12 and we previously started reading Slaughte-rhouse Five. So far the novel is of a different format. Kurt Vonegut decides to tell the audience what the novel is about in the fist few chapters, giving away keys facts such as the climax, where Edgar Durby dies in Dresden. I'm not sure what to conclude from Kurt's plot sharing but it seems to be a sucessful tactic because his book Slaughter-house five is read in twelth grade english classes around the globe.