I like the 'open class' format where you bring something to work on and get help with it as you need it, and everyone gets to know each other so it is social, and we help each other as well. You would be surprised at the variety of projects people bring in, from bags and bowls to applique to red-work and paper piecing and huge pieced quilts. It can be more of a drop-in which is great for working people.
I don't like "Make This" classes where you have to buy the package of material and pattern from the LQS, show up and do all the work right then and there. Sometimes I am slower than others and I get behind. Plus these classes - though they use a technique I want to learn or improve at - have a really dorky pattern or colors. Too structured for me!!!
I also don't like classes where there was a little clique of quilting-guild types who already know it all and are there to show off to everyone / bug the instructor while I'm struggling along trying to learn something.
If you are doing a make-something class, try doing it in the fall for Christmas gifts, and make it quick, painless and clever, like those fabric bowls, or a bag or potholders or whatnot where you can chose the fabrics. And avoid classes requiring some dumb ruler you'll never use again.
Love the suggestion from poster above about discounts for all fabric bought that day - definitely saw this successful at my local LQS!
I think it is great that you are not only skilled enough to teach but good enough to want it to be a great success for the good of the LQS.