This study investigated how school leaders engaged in agility practices during crisis. The study outcome is hoped to help generate an in-depth understanding, rich description, and new proposition of leadership agility in school leaders. Using grounded theory approach, this study presents findings from semi-structured interviews with 28 participants. By using the qualitative software tool NVivo 12, the study builds on theme constructs of resources readiness, crisis strains, leaders’ agile capabilities, and crisis solutions. Key findings elaborated from the themes include the staff digital competence, school infrastructure, learning loss, lack of personal connection, leaders’ agile capabilities, support of school community, and school leaders’ ability to build the culture of collaboration during crisis. The findings presented deeper insights on how the school leaders led their organizations during a crisis and how their agile capabilities which are represented by their ability to adapt, being flexible, active learner, being a role model, and having future – oriented mindset is crucial for use during periods of novel crisis in schools. The identification of how the agile school leaders led their schools during a crisis could help fill the existing gaps in agile school leadership under the context of COVID-19. For future research, an approach using quantitative instrument may help support the testing and further elaboration of research developmental models obtained based on qualitative data in this study.