I see nothing wrong with them discussing things as long as their online relationship doesn't become too emotional or personal. A good teacher is likely to instill some of his/her own interests into their students, and for the student it could be a great help to get the teacher to speak to them one-on-one about a subject they are trying to grasp better.
I think it would be better to become friends with them, on social media, after you are not taking a class they are teaching. Enough teachers are getting in trouble for having sex with a student because they were not doing good in a class. I feel it would be another way to bribe a teacher, find out their favorite foods or even where they live it is a student and teacher safety issue.
It really depends on the relationship between the educator and the student. I definitely wouldn't recommend social medias such as Facebook, but since social media is becoming an important role in curriculum, I don't see why it's a huge deal. Usually if the teacher is friends with the student on social media, they really don't even pay attention to most of their posts, they just want to be available for their students if their students need them.
Look, I can understand if this was to monitor the progress of a student's homework or to ask questions, or keep them updated on events. But a fine line needs to be drawn. As I scroll through my news feed on Facebook, I'm constantly noticing status updates and even, get this, recent articles that my friends have either liked or commented on. That's what irks me... Not just as a Facebook user, but as a human in general. The key word here is Privacy, and we seem to be loosing that as well.
If teachers are friends with students they have the right to go through there stuff. I mean to be honest would you like a teacher going through your stuff?I just find it inappropriate.If they want one on one thats why they have emails.I mean use some commen sencse please ok