I made that mistake on my first class - letting the students know it was my first class. It just seemed natural during the introduction - as everyone was telling about their history and goals etc., to say I've done this for so many years - and now I am an instructor. This was with a group of first-time college students as well - and thought that the line, "It's all of our first class, we'll be learning together." might work... it did not. I've since learned to leave that part out of the introductions (though I suppose after that first class it no longer applied anyway). I never thought of it the way it was presented in this course - about creating a confidence gap. It seems that omitting this fact gives you an instant confidence boost in your student's minds much more so than if they know it is your first class as well. How many others have made this mistake?