You may find it worthwhile to reach out to local community colleges, because once you're "in the group" you can find people doing various things, and they're often not advertising, but will be willing to take a bit of cash on the side.
You tend to have some younger screw-up, unmotivated students, especially at entry level classes; some younger students that are there for economic or other reasons; some older students going back to school for life reasons; and then some older students who are intellectually curious and doing it for enrichment.
What the make-up of a class, and the resultant culture is, is a crapshoot. But it can be outstanding.
If you avoid the standard college classes, you get a pretty wide cross-section of the people in the community. Math 101 is mostly going to be college-age kids.
Heck, even my Bio 101 professor was abnormally brilliant. She'd been a researcher at Harvard Medical School who worked on highly experimental treatments in a ward full of terminal patients and just finally burned out from being around so much death all the time, so there she was in Los Feliz three blocks from Scientology world headquarters teaching at a community college, probably the hardest class I've ever had to take.