When I went back to school one of the courses I had to take was speech. My instructor found it amusing that I taught for a living but was unable to participate in the class without freaking out each time I had to speak. I even used one of my lessons as a speech and still struggled. For me it is not the lack of knowledge that did me in but the feeling that I am being judge. When I reach my students are so eager to learn that I am not aware that I am talking in front of 30 people. I feel that I am just talking to friends that want to hear about ECG's.