I had a teacher who was continually racist towards students. He swore at kids and made fun of them for how looked. Here are some direct quotes (in a carribean accent):
"hey student 4 how is puberty going",
"hey student 3, you're a dickhead and your brother was a dickhead too",
"student 5, you're a fucking wanker".
The best part was that everyone found it funny and he has worked as a teacher for over 15 years and still works as a teacher. He also liked picking on quiet students.