Few studies have been conducted on types and characteristics of classroom disruption in South Korea despite a large amount of discourse concerning many students repeatedly interfering with class in secondary schools. Addressing this issue, this study sought to answer the following two research questions by observing middle school classroom teaching over two semesters in 2019. This study first investigates what the typical types and characteristics of classroom disruption are. Second, the study examined the types of students engaging in classroom disturbance. As a result, this study shows that students participate in low-level disruption such as chatting with one another, teasing, and making noise, which could be mitigated by a teacher s warning. On the other hand, serious patterns of classroom disruption occur with misbehavior such as wandering, interfering with the teacher s instructional plan, ignoring the teacher s instructions, and leaving the classroom. These students were categorized into several types: high-achiever disengagement, low-achiever disengagement, students with negative attention-seeking behaviors, and students who bring problems from home. In summary, whether to participate in classroom disruption is not always something that has to do with the student s level of achievement; however, there was a difference in ways of disrupting classes according to the level of achievement. Overall, students are continuously and invisibly compromising with their teachers during class, which can be referred to as class engagement with relaxation or relaxation with engagement. This study contributes to better classroom management by revealing what actually occurs in the classroom with respect to classroom disturbance, considering that today the relationship between teacher and students is more democratic, part of which previously displayed authoritarian control, including corporal punishment.