Censoring Novels

In one of my classes this week we discussed censoring novels.  We specifically talked about schools censoring Twain's Huckleberry Finn because of its racial references.  I think this book is usually taught in middle school so I can understand censoring it, but I don't feel that it's necessary.  More than likely, students have encountered these issues before middle school, so why isn't it okay to talk about it in a controlled setting?  If approached correctly, which includes teaching some history of the issue, I feel that it would be a good lesson for students to learn.  I heard that one school allowed their students to read the book but they were not allowed to read it out loud.  This is just avoiding the issue.  What are students going to learn from this?  However, I didn’t read it in school so I’m not sure how I would feel as a middle or high school student.