Why should huckleberry finn be taught in classrooms?

As it is banned around schools everywhere, it should be taught to show students the past. Teachers who are teaching it still with advisory from others have stated that it is the best read of their career. The students enjoyed it and the teacher enjoyed it as well. The book has children who are rebellious, illiterate, and more. Students enjoy this book, so why ban it? Officials banned this book due to its somehow racist language and think it's inappropriate for children. Children aren't the ones reading it, it's normally students over 10th grade. As if we've never heard any of these words before or faced these problems.

-Mabel <3