Final answer:
Being expelled is a school-related reason for leaving school.
Step-by-step explanation:
A school-related reason for leaving school is being expelled. When a student is expelled, they are removed from school due to a serious violation of school rules or policies. This can include behavior that threatens the safety of others, such as violence, drug use, or other forms of misconduct. Expulsion is a disciplinary action taken by the school administration to maintain a safe and orderly learning environment.