Robert Prather of Insults Unpunished links to a WaPo piece on a list, compiled by conservative stuents, of ten UT-Austin professors who allegedly use their classrooms as a forum for proselytization instead of teaching.
I do think it’s sometimes a professor’s job to challenge the views held by their students, to ensure that they are actually considered viewpoints; however, there’s a difference between that and becoming an advocate. Particularly in large lectures, where there is often little time for discussion, and where there may be an incentive for students to try to curry favor with the professor by claiming to share the professor’s views, I think it’s best to avoid advocacy.
My cardinal rule in the classroom is to keep my students guessing; the highest compliment I’ve received was from a student who indicated that she and some of her friends couldn’t figure out what my politics were—which, I think, means I was doing my job just fine.