I never liked being told what to do, so when I was told to read a book in school, I wouldn't read it unless someone could give me some explanation of why it should be read beyond "for the class". I got through high school having never read a book I was ordered to. The oddest part was that I held to this rule even if I actually wanted to read the book. I'd just wait. So it was with Animal Farm. I didn't read it until a few years after we went through it in school, but I still remember the discussions we had about it in class.
Now, on this re-reading, I am struck by how wrong most of our discussion were. I don't know if my teachers didn't really understand the book or if they were intentionally distorting it's points. It's not anti-dictatorships, it isn't really even anti-communism. It's basically just anti-Stalin. It's hate mail for Stalin. Fun to read, and an interesting approach to dealing with some of the history (in fable form), but it doesn't really go deeper than just an intense dislike of Stalin.
Orwell was notoriously anti-totalitarian (see 1984), but what was whitewashed from my education on it (in America) is that he was also a devoted socialist.