Wife GF but NO MILF!
I don't get it!
You gotta do what you gotta do, even if that involves dealing with your girlfriend's mother. lolhaha thats funny man. hey, its business.
I'd record the class and take lots of photographs, and if possible hide a camera, then establish myself as an authority in the niche. Sell video courses, ebooks, and make a badass emailing list which I'd monetize by selling "how to make a solar panel" type products.
fail.