I tried setting up a page just for students one time, but rarely checked it - I found the spelling errors, status updates of "I'm bored" and the games tedious. Then I felt bad because one girl had messaged me and I hadn't checked in two weeks. It kind of scared me because if it had been an emergency (For example: help me my step dad is_______ or I am so depressed______) I would have been liable.
I absolutely wont have students on my FB page because they really do spam your page and I dont want them in my business. That said, I teach sixth grade, if former students are upperclassmen at high school, or out of high school I DO friend them. I also friend any of my daughter's 15 year old friends that ask (some of them former students), just to keep on top of things.
As far as parents go, I often friend them... only the ones I like
Finally, you should google "teacher fired for facebook" there are a lot of cases out there. Lots of districts have social media policies - you should check.
This is one thread about FB... couldnt find the other one, but this has been discussed before.
http://www.proteacher.net/discussion...d.php?t=337414