If all else fails in dealing with misbehaving kids in public (question from last post) you could always try pulling out the camera and taking a picture:Yeah, it doesn't work so well to get kids to calm down but for some reason it makes me feel better...(that post is here).
I'm kidding, a little bit.
Actually, the very best thing I got reminded of from a comment in that last post is the "start over" tactic my parents used to do. If a child starts acting up or talking disrespectfully we just stop and say "let's start over," and then we do. We start the conversation all over again from the beginning and let the child choose to respond a little bit better. It's a good training tool I wish I'd remember to do more often.