Teacher first, friend second

This seems to be my mantra lately. I like befriending students and being 'chummy' with them but I've found that this tends to blur boundaries that need to be clearer. In my quest to raise standards of scholarship and study at my school, I've found myself being a bit more of a hardass towards our students and this has been a bit uncomfortable to deal with. I don't know if it is because it maybe seems unexpected from me ("he yelled at me! he's never done that before) or if it is because it is new for me (in the past I tended to flinch first). I'll cut to the chase: this week alone, I managed to express supreme dissatisfaction of effort and results to four students, two of whom I brought to tears. One of these episodes included a raise of voice that hasn't happened in at least three years (when I had to deal with a certain bull of a student who has turned out to be a mouse). I can't say that I wasn't justifiably prompted to be harsh and stern. However, I still am feeling very awful about how this week went down in general.