Overheard in my car today

1st and 7th graders are having a conversation about "cuss words".

7th: Don't stick out your middle finger, it stands for something not nice.
1st: Why, what does it mean?
7th: I'm not sure, but it is a bad word. (Mom sighs with relief that 7th is still a little naive.)
1st: Lots of kids at school use bad words, they use the s-word a lot.
7th: You mean (spells out s-h-*-t) ?
1st: Yep, they say shut up all the time! (Mom laughs, glad that 1st is still very naive.)