There's this little boy John and one day he goes up to his mother and asks:

"Mom, how old are you?"
Mom: "Now, now, John. That's a personal question. YOu don't ask those kinds of personal questions to women."

"How much do you weigh?"
Mom: "You're too young to understand that you don't ask those kind of questions to women."

"Why did Dad leave us?"
Mom: "your too young to understand that too, I'll tell you when you're older"

So John goes back to school and tells little TOMMY: "TOMMY, my mom doesn't want to tell me how old she is or what she weighs. She doesn't answer any of my questions"

And little TOMMY replies: "you should go into her wallet and look at her driver's license. All your questions will be answerd.

So John goes back home and look into his mom's purse and looks at her driver's license and goes to his mom:

"Mom, you're 39 years old."
Mom: "Yeah that's right I am."

"And you weigh 142 lbs."
Mom: "yupp that's right."

"One last thing... I know why dad left us." Mom: "oh really, why?"

"Because you got an F in sex"