Tea at Teatimeramblings has a Mother of the Year Award and I am not sure that the following is a winning story, but it's a conversation that I will never forget.
When #1 son was 12 years old after having taken "health class" where he learned the school's version of Sex Ed, he asked me what PMS meant. I went into great detail about the hormone changes that women go through each month and that sometimes the week before, women become more irritable. He then said, "Well then you must get it twice a month." I let him live.
He doesn't remember the conversation, but it's one that I remember with a smile.