F Grade

A mother is driving a little girl to her friend's house for a play date.
-Mommy, the little girl asks, how old are you?
-Honey, you are not supposed to ask a lady her age, the mother replied. It's not polite.
-OK, the little girl says, How much do you weigh?
-Now really, the mother says, those are personal questions and are really none of your business.
-Undaunted, the little girl asks, Why did you and Daddy get a divorce?
-That is enough questions, young lady, honestly! The exasperated mother walks away as the two friends begin to play.
-My Mom won't tell me anything about her, the little girl says to her friend.
-Well, says the friend, all you need to do is look at her drivers license. It is like a report card, it has everything on it.
-Later that night the little girl says to her mother, I know how old you are, you are 32.
-The mother is surprised and asks, How did you find that out?
-I also know that you weigh 140 pounds.
-The mother is past surprised and shocked now. How in heaven's name did you find that out?
-And, the little girl says triumphantly, I know why you and daddy got a divorce.
-Oh really? the mother asks. Why?
-Because you got an F in sex.