Late bloomers:

"Late bloomers are certainly not ordinary as children - they show unusual interests and high levels of curiosity - but no one would predict, from the child, what the adult would become. Often these children discover their domain in college, where they are first introduced to it. They then take off, looking much like prodigies who discovered their domain in childhood. These individuals typically master their domain virtually on their own, refusing to conform to the demands of the college curriculum, or even dropping out of college, as, for example, in the case of Bill Gates, the founder of Microsoft; Edwin Land, the founder of Polaroid; or futurist and inventor Buckminster Fuller."

Ellen Winner, Gifted Children