difficult students
never discuss the student in front of class, ask student special assistant
I agree with what you wrote. I will talk to students before class, during break times and after class either in my office or some place quiet and private. Lots of times students have issues and don't know where to go to get help dealing with them. Most of the time I just listen to them, and then send them to their program chair or advisor. Afterwards they seem to behave much better in class. I think it is because I took extra time with them.
One way I've learned to deal with difficult students is to call the student outside of the class and talk to the student in private. When calling the student out in class seems to make them more aggressive. Try to find out what the problem is, resolve it, and it that doesn't work send the student to someone by chain of command.