I was going to mention the fire drill we had about a week ago, and then things got busy (two tests and two sick kids this week alone!) before I had a chance. So here goes:
First of all, I think all those false alarm fire drills we had as kids have really helped. They always say in the event of a fire not to panic, stay calm, and head for the exit in an orderly fashion. I can't say how orderly we all were, but there was no panic, that's for sure. Mostly just groans and sighs followed by a slow exit. I felt very safe.
Also, the groans of disbelief definitely had different timbres to them. For the professor, it was like, "Oy, I am never going to finish this material by the end of the week," and for my fellow students it was more like "Seriously, I have to get up? Hnnngh."