heh, get "Lies My Teacher Told Me: Everything Your American History Textbook Got Wrong."
PhotoRead that, and then be a little monster in class.
For biology, check out Gould and Lewantin. (I may have the spelling of the former quite mangled). FACT: Gregor Mendal faked his famous pea experiements to get the results he wanted. Most biology teachers are going to be leary of having you mention things like "Telegony" or "cytoplasmic inheritance," but what the hell? There was a recent study done that proves part of human gestation involves the mother's genome takes on part of the father's - via the intercession of the child. It's one of the reasons the immune system doesn't flat out kill the baby. Dog breeders know about this (once a female dog has puppies with a non-purebred, the mother is no longer considered purebred herself), but you sure as heck won't find it in any text book on biology.
Remember, if you're going to be "smarter than the textbooks," it will give you an advantage of having a reputation to live up to, but make sure to live up to it!
Where there's a Will, there's an A.