The Great Gatsby. I never had to read this in school. We got to read Frank Herbert. Changed my life.
One of my brother's lit teachers thinks however, that this is the greatest novel of all time and that it is a stellar commentary on class and society. So I read it. And then flipped through it to make sure I hadn't missed anything. Guess what? I don't think the people who read this book and think it's great, actually know what the author was trying to say. It looks like he was really trying to say "Fuck everyone, fuck off." and people somehow got confused and considered gatsby a hero of some kind.
I had to read the Tropic of Cancer. What a pathetic and thinly veiled attempt to shock people, while claiming that it's intent is not to shock you with such a mundane word. Well if **** is such a mundane word, why the hell did the author find it necessary to use it as noun, verb, adjective...the book isn't even any good if you replace the thousands and thousands of the word's usage and try to come up with something interesting on your own.
I think people call them classics because let's face it, it's not like there were thousands of authors back in the day like there are now, it's not like some shlub with a good story idea would have been able to write, print and distribute his book on his own. Back in the day you needed connections and money. Hell, even until about 1970 you could barely get published unless you have a degree from a university, or wanted to write complete trash for a pulp company.