Little Johnny drew a fly on the class grade book.

The teacher noticed the fly sitting on the grade book, so she smacked it with a ruler. But, the fly didn't fly away, so she smacked the grade book once again. Again, the fly didn't fly away.

This drove the teacher mad, so she started to pound the grade book with the ruler and, as a result, the grade book quickly amounted to nothing more than a bunch of torn sheets of paper.

With the class laughing, the embarrassed teacher realized what had happened.

That afternoon, the teacher called Little Johnny's father to school., "You see what your son did to our class grade book?" she said.

"That's nothing," remarked Little Johnny's father., "Last week, he drew a naked woman on the fence in our yard and I've been pulling splinters out of my dick ever since!"