A thousand people have said this before me, but THINGS FALL APART is truly a wonderful piece of fiction. From the first pages, you are immersed in a beautiful, strange (to me, anyway), fascinating culture that comes through in every description, in the words that come from the character's mouths, in the conflicts between individuals and the clash of cultures, and especially in Achebe's direct, articulate, sparesely beautiful style.
As other reviewers have noted, it's usually not the best when you're being forced to read it for a class. But look at it this way: most books aren't. If you're in that situation, try to get past the coercion factor and the problem of grades, and read this book for yourself. It's a "classic" -- that's why they're making you read it -- and no one hates "classics" more than I, but THINGS FALL APART is much, much more than a "classic" work of fiction. It is a tragedy, deeply felt, that draws an unerring portrait of human nature and especially human conflict. It is a good story, and one beautifully told. It is an education you owe to yourself. And if that's still not enough: it's short.