I think it is very important to know how your students learn. In my classes, at the beginning of term, we do individual assessments to make sure that the students are studying correctly and getting the most out of their hard work.

I find that angry students really just want someone to listen and hear what they have to say. When I notice a student is acting out, I like to pull them aside after class and give them a chance to discuss any issues they may be having. Most of the time, they can vent and feel a lot better.