A 13 year-old boy comes home from school and his mom ask how was his day was. He replies, "I had sex with my teacher today."
"Oh my god! You get to your room! Wait for your father to get home!" says the mom.
Awhile later the father comes home and the mom says, "Go up to your son's room and talk to him, he's been really bad today. Dad goes up to his son's room and asks why mom is so mad.
"I told her that I had sex with my teacher today," replied the boy.
"Alright! That's my boy!", says dad. "Ya know son, women just don't think like men. But I'm proud of you. What are you now, about 13, right? Wow. That's my son! Ya know what? I'm so proud of you I'm gonna take you out and buy you that new bike you've been wanting!"
So the dad and his son go out and buy the nicest, reddest, shiniest bike in the whole town. "You gonna ride it home son?" asks dad.
The boy replied, " Nah, my ass is still sore."