Teacher asks student if he knows his numbers, but the boy's response is unexpected

It's Clyde's first day of grade school after being homeschooled for several years. The teacher asks the young boy if he knows his numbers.

"Yes," he says. "My daddy taught me."

"Can you tell me what comes after three?"

"Four," answers Clyde.

"What comes after six?"

"Seven," answers little Clyde.

"Very good," says the teacher. "Your father did a very fine job. What comes after ten?"

"A jack," answers Clyde.