I just tried to have a discussion with one of my classes that was absolutely ugh. Only a few people spoke, and I wasn't leading well, and just ugh.
Partly, it's the beginning of the semester thing where some people are intimidated now, but will be able to contribute in a week or two.
Partly it's the beginning of the semester thing where some people just aren't used to reading carefully yet, and so disagree with something the author didn't actually say, and want to talk about how wrong the author is, except s/he didn't say it anyway.
Partly the room is a really bad configuration for good discussion, and way crowded, so circling up isn't really an option. It's a long narrow configuration with a lot of bodies stuck in.
And partly I just stunk at leading today, despite being pretty well prepared.