"Alright class we will move onto sex education", says the teacher
The teacher then goes up to the blackboard and draws a huge penis and says, "Can anyone tell me what that is?"
Dirty Johnny stands up and says, "Yeah I can tell you what that is, it’s a penis, and you know how I know, my old mans got two of them."
Teacher says, "Two of them, are you sure son?"
"Of course I'm sure, the little one he uses to pee and the big one he uses to brush the babysitters teeth!"