So, here's a new problem: a student who makes sly remarks to the person sitting next to her. No, I'm not saying my students have never done this behavior; it's just that in the past such a student might remark to a friend that the teacher is boring, or the material covered stupid, or whatever. That's normal. We all do it (admit it--you've even done it in a faculty meeting).
No, this student remarks to others who have no interest in her opinion. She also manages to be disruptive by not really getting what's going on, but thinking that she does. Recently, she was involved in two incipient snit fights. And when I suggested she not engage, she was insistent that she was in the right. As did one other participant.
But "right" isn't the point here. And I found myself falling back on the "It's my class and I'm in charge" speech. In my defense, I wasn't feeling well, but still. I gotta have something better than this.