Kids like that tend to think that studying/practicing IS part of childhood:) The whole concept of tossing a ball or running around with no purpose is silly.. sort of like coloring by number. What's the point? You cannot force a child like that to play like a typical child, not without a bad reaction. They will close down even more to what you would consider normalcy. Or - and this is even worse, maybe - they will force themselves to adapt to a societal norm to please the parent or teacher but in the process, lose some of the drive in their interest area. Leaves them somewhat lost as to their place in the world.
It would be like sticking a "normal" kid with a group of Downs Syndrome kids, and expecting him to act like them
Visualize living in a world where mental retardation was the "norm", and you'll start to understand why so many child geniuses don't turn out so well