I think that recording sessions should be allowed because it's more effective as far as learning, and after they take all the notes they missed during class they could delete them the next day if the teacher/professor would feel uncomfortable with them being recorded
This should not be allowed. One reason for this is that writing notes by hand helps you understand the topic more. If you have to study for a test, and you recorded a lecture, you would have to review the entire recording, which may reduce the amount of sleep you get, and the effectiveness of your learning. Even if recording a college professor's sessions were beneficial, what if someone could not afford a recording device? Would this be fair to those who are poor? This is why I believe recording college sessions should not be allowed.