About creating interest, my opinion is that teaching as a first step is not the answer. It is necessary to capture people's attention and interest first and I think a big issue is to let them know that it is something simple and that there is no need to have a previous background or special habilities. With that understood, instruction (or self instruction) may follow. I think a big reason why people choose motor boats instead of sailboats is that it seems to be fun and simple enough for anyone.

I lived for 6 years in a town in Chile called Los Angeles, where once a year a beneficial institution organized what they called "popular flights", where people could pay a very reasonable fee to get a tour of the area in a small airplane. The institution would get funds, the airplane clubs would perhaps get a piece too, but would also have an opportunity to show their activiy and perhaps do some free flying hours for their members and who knows what other benefits (don´t know much about flying, except having experienced a couple of flights with them). A similar idea could be applied to sailing. I think a key point is not make sailing the only or the main purpose of the activity (in the case of "popular flights" it was a benefical purpose), because this way you eliminate the need of having at least a minor previous interest in sailing, which could reduce the amount of people and let out some potential new sailors.