GWS :: forty-five
What Lore Rasmussen found, to her great interest and mine, was that even after doing a particular worksheet completely correctly, a child might do that same worksheet half a dozen times or more before moving on to something else.
Apparently the children got much pleasure and satisfaction from doing something they had struggled to do the first time more easily and confidently each time.
Only when it became so easy that it was boring did they decide that they had enough–and they were the best judges of this.
–John Holt in Growing Without Schooling