Smart people can also find grade school to not provide enough challenge and complexity and thus they tend to find other ways to occupy their time. In college the scene changes because you pursue what you want and most professors recognize true interest over mere putting in time to complete a class for credit. The moment you find a professor who recognizes your interests, keep a close relation because they can help you in more ways then you can imagine.
Sadly college still does not provide enough of the "real world" to make much a difference. The college I went to, at least, seemed to be more interested in grooming me to be a researcher which is why I found most of the CS classes to be extremely boring.