Here are my observations from backstage:
1. Whenever you have to keep a group of kids quiet, it helps to start with the assumption that you're going to have to say "Shhhh!" about 100,000 times. That way when you hit "Shhhh!" number 87,256 you aren't annoyed, because you still have a long way to go. (This approach is good for things like getting your own kids to chew with their mouths shut, too.)
2. The techniques that work for getting a message through to three and four year olds work for eleven and twelve year olds, namely, a) insist on eye contact, b) put your hand gently on their arm while you're talking, c) require a response.
3. Walk toward the troublemakers. It's a subtle thing, but a lot of crowd control can be done wordlessly. If you're right next to a difficult child, she's far less likely to imagine she's unmonitored or free to ignore whatever you just said.
4. People who teach middle school are to be admired.
And now back to the work that piled up last week!