Well thank you for bringing up such a topic
and i think that these aggressive actions will mostly come up because:
1.the student wants to act cool and daring
2.the student is in bad mood
3. a teacher or a friend provoked the student to do so
4.family arguments and long term issues will cause the student to always have an aggressive and negative respond to different situations
and sometimes even
5.an emotional break up with a girl friend /boy friend