I have actually already done this. I took Teaching Techniques last year (due to my mid-year performance/education crisis), and had two occasions on which I had to be the teacher for the class and announce my name and stuff.
I would like to think that I was calmer this time. I saw the video of the time I taught rote songs to the class, and I kind of slipped into musical-theater-performance mode... you know, bright smiling face, enthusiastic voice, moving energetically.
I believe someone made the comment that I looked as if I was "hitting my spot" when I would move about the room.
But I think I was calmer this time.