Again..totally agree with quiltmom. Make it clear in your printed information that you do NOT teach them how to use their machine or "borrowed from my Mom, how do I thread it?" I too taught a lot of classes and my beginner class was the most popular. I would suggest the next class to them after I saw how they did with the beginner class, as some do better than others.
Your jacket is beautiful and by all means, take some of your other sewing/quiting work to the shop when you go. I hope you'll keep us posted on what happens.
Don't let all of this talk discourage you, Sparky....just go for it. We all learn as we go along, and the same with teaching what we know.