Ooh we had a teacher at secondary school and the poor woman had to deal with our class last double period on Friday afternoons three years in a row, and all three years we had just either had sport or cooking or music or art or whatever so were all hyped up.
We were awful to her and we used to play a kind of bingo with how far we could push her. Certain swearwords were a certain number of points, stamping her foot was another. Tings like raising her voice or getting stressed and playing with her hair were just one point but it happened so often we couldn't leave the lesson without getting 50 points. And we were a good class, everyone else loved us, but she was so easy to wind up that we just took advantage 
My French teacher OTOH was one of those unflappable teachers hardly ever had to raise her voice she just exuded discipline and the day she swore at us we knew we had gone too far.
Oh happy days. I hated school.