Of course this is not possible at school.
But the illusion that lessons are play cannot be indefinitely kept up, or if the illusion remains it is fraught with trouble.

Duty and endurance, the power to go through drudgery, the strength of mind to persist in taking trouble, even where no interest is felt, the satisfaction of holding on to the end in doing something arduous, these things must be learned at some time during the years of education.

If they are not learned then, in all probability they will never be acquired at all; examples to prove the contrary are rare.

The question is how--and when.

If pressed too soon with obligations of lessons, especially with prolonged attention, little anxious faces and round shoulders protest.