If this isn't the right place to post this, then my apologies. I have a friend who's a teacher/SMT in Thailand and the school has a thin client set up with 20 terminals, and as he puts it,
"The problem isnt the students using Facebook.............the problem is the teaching staff using Facebook when they should be preparing lessons/marking books/grading tests etc!"
Is there any way he can block certain sites on the server?

