Any teacher's nightmare!!!

If there is one thing that I've been dreading is for my students to do something inappropriate in front of the principal to make me look like an idiot. Well, how about the principal AND visitors (probably prospective teachers)? Of course mine did. Why not? Let's make the rookie look like a fool. It was one of those Southwest Airlines "Wanna get away?" moments. The principal is giving some people a tour of the school and we're coming back from lunch and my kids are bunched up at the door fighting over who holds the door (apparently they have amnesia and forgot that the line leader holds the door). He does the sign we use at school for silence and my kids quickly respond and get in line. Some are still wispering and he asks, "Where is your bubble?" (they all puff up their cheeks and get quiet)...All but one little punk who says, "In my booty," and turns his back to the principal and walks to the end of the line. So this is where I want to crawl under a rock. I call the student over by me and tell the rest of the class to go into the room and sit on the carpet.
The principal took him aside and asked him to apologize to the ladies and took him to his office for about an hour. I think he called his parents. He hasn't told me if he's giving him a detention or not.