This study aimed to examine the impact of COVID-19 on the pattern of socialemotional development and learning engagement of Korean students. It employs latent profile analysis to categorize middle and high school students based on their social-emotional development (action-orientation, optimism, perseverance, relationship with adults) and learning engagement (cooperative learning, and self-directed learning). The analysis, conducted during the fall semester of 2019 and the spring semester of 2020 amid COVID-19 school closures, explores nuanced patterns and effects. The findings reveal distinct student groups with discernible differences across all factors both before and during school closure. Notably, the research suggests that early social-emotional development may influence subsequent developmental stages and that a student's social-emotional skills correlate with cooperative and self-directed learning. Furthermore, the study highlights the pandemic's varied impact on student groups, indicating that those with advanced social-emotional competencies and established learning practices were resilient to school closures. In contrast, 'average' students faced challenges in cooperative and active learning during lockdown. The study underscores the need for targeted educational measures, particularly for at-risk students, and suggests proactive preparation for future pandemics.