I haven't made a post here in a while either, so I thought I'd start again with something that's a bit more controversial. It's well established that, unless a certain course is required for a plan of study, a student is free to refrain from taking courses from a certain professor. However, the opposite is not true. If a student is not required to take a certain course, a professor generally cannot "opt out" of having the student in his or her class. Now of course if a professor is just allowed to prevent students from taking a course carte blanche this would be a very bad idea. The opportunity for discrimination of many kinds is very present, to say nothing of professors summarily refusing students to keep grading loads down or professors refusing students who know more than they do in order to avoid accountability to the class.
But we've all had students who go through one of our courses that aren't outwardly disruptive but are certainly corrosive to the course. I figure we should be required to have those students the first semester they take our courses. It's such an unpleasant experience for all involved that it's hard to believe anyone would want to repeat it. And yet, bafflingly, sometimes the name appears on the next semester's course roster. Just when one is ready to start with a clean slate and forget the previous year's trials, there is the whole problem threatening to repeat itself.
I'm pretty sure the answer here is that the potential for abuse far outweighs giving professors even a curtailed right of "repeat refusal". But there are cases that make me want others' input, like very vocal students who do none of the work or do it very poorly, plagiarism cases, or students who walk the disruptive/disrespectful line with great skill. And these problem students can loom very large when one has new or deserving students who need a slot in a full classroom. Thoughts?