Lil' Johnny and his friend were at school and heard the word "penis" while they were playing on the school yard. Johnny's friend asked him if he knew what a penis was.

Lil' Johnny said he didn't know but would ask his dad when he got home.

That evening, Johnny asked his dad, "Dad, what's a penis?"

His father said, "Son, I'll not only tell you, I'll show you." So they went into the bathroom. Pop lowered his pants and proudly announced, "Son, that's a penis. Not only is it a penis, but it's a perfect penis!"

The next day at school, Lil' Johnny found his friend and took him into the bathroom. Johnny lowered his pants and said, "See that? That's a penis." He paused for a moment and added, "Not only is it a penis, but if it were two inches shorter, it'd be a perfect penis!"