This is an ambitious idea...
As a beginner, what I would find useful, either at a good LFS or a club community site is a set up that emphasizes the need to be patient when setting up a tank and teaching the nitrogen cycle. I could imagine that there might be four (or so) tanks showing various phases of development (including signage which someone would have to keep up with -- things like DIATOM BLOOM - DON'T PANIC!; perhaps even post the most recent water test results). Please feel free to correct these phases:
Phase 1: mix saltwater, add substrate and live rock (including how to glue pieces together) and necessary equipment, begin cycle
Phase 2: test water and monitor cycle
Phase 3: add clean-up crew
Phase 4 - ? : add livestock (acclimation, gluing, etc.)
I could see a good LFS or club offering free workshops such that a cohort meets for class and "works" on their tank (work may equal the instructor doing a live demo) as it progresses (or I suppose you could just let people jump around and pick and choose which phase they want to learn about). By having multiple tanks in progress, they can see the future phases to come, and these other tanks may also motivate purchases at the store (or memberships in the club, basically growing the hobby). If the thanks are set up in a community area, the public may be inspired to take a workshop as well. If this was run by hobbyists, and you had a large enough group, you might be able to run group buys.
I suspect many people just buy all the stuff, put it together and jump into trouble.
I would say there are advantages to doing this as a club and advantages to doing it at a good LFS. I have not been there, but perhaps Sci-Quest would be interested in providing some space. ("Sci-Quest strives to ... be a community resource for informal, hands-on science education."). It would probably be better at some place that wouldn't want to charge admission though.
Just throwing the idea out there. I don't know enough to teach it, but I can help someone develop the curriculum, create handouts, etc. (I have an M.Ed. in Curriculum and Instruction that I'm not using.)
(Full credit: idea partially inspired by the workshops run by the Apple store:
Apple Retail Store - Workshops )