High School Mischief(1992)

Original title: 장닭(정명현) 고교얄개

Du-su is a mischievous high school student known for causing trouble at school. After one of his pranks leads to a fellow student being ostracized, he publicly apologizes and tries to make amends. Through a series of disciplinary punishments and unexpected responsibilities, he gradually becomes more aware of the impact of his actions and begins helping those around him, including a lonely elderly man and a struggling classmate.