In fact, you don't need to send your child to school, just find someone who can play chess and tell him, such as riding a horse (in the sky), flying an elephant (in the field), shooting three turns with a gun (that is, separating a pawn, whether it's the enemy's son or his own son), driving in a straight line (the enemy's pawn that stops can be eaten), and soldiers can only walk ahead step by step before crossing the river, and can only walk sideways step by step after crossing the river. He knows these methods, and it is not too late for you to let him go to school.