If you made the strongest kid in school sit on a stool all day, while the rest of the class pumped iron for hours, in a few years he won't look so strong compared to to his peers... unless the kid secretly works out at home on his own. That's pretty much what they do to our children in K-4.
Reminds me of my child getting "in trouble" for working ahead in math... he was/is suppose to sit there for remaining time once he has mastered the work and wait quietly.
He was desperate to learn more math do somethign in math more challenging...so now we "work out secretly at home" after being told that again next year that there will no ability grouping in math and they'll provide him differentiation as/if they see fit.
