The WSJ writes on some new studies on academic bias. Among the other interesting points:
For instance, nearly half said that their professors "frequently comment on politics in class even though it has nothing to do with the course" or use the classroom to present their personal political views. In answers to other questions, the majority acknowledged that liberal views predominate. Most troubling, however, were the responses to the survey item "On my campus, there are courses in which students feel they have to agree with the professor's political or social views in order to get a good grade"--29% agreed.