For those of you who are unfamiliar with Grub Street, it's been around since 1997 to create a supportive writers community. Over 2000 students have taken workshops and classes with them, and their alums have gone on to attend top MFA programs, publish books and sell screenplays.
As for myself...well, I've taught a science fiction and fantasy writing workshop a few times. I taught it three times at the Cambridge School of Weston, and then I taught smaller versions for other students. I also did two one-night workshops for the Harvard College class The Anthropology of Science Fiction.
If you know of anyone who might be interested in taking the class, a description of the course can be found here. It'll be a workshop class, but each night I'll also lead a discussion on various aspects of the genre, such as space travel, time travel, world building, mythology, etc. You can also see Grub Street's full Workshop Schedules and information on tuition and registration, in case there's another class that interests you.