The exceeding importance of academic optimism and the promising potential of middle leadership demand research attention in contribution to student success and school improvement. This paper presents a critical analysis of the roles and contributions of middle leaders through the lens of the academic optimism model. This study used mixed methods with a nonexperimental, exploratory-sequential approach (case-selection variant), identifying best-case participants and featuring qualitative findings through semi-structured interviews with six public-school department heads. These participants represent two high, two average, and two low-optimistic departments. Findings revealed that middle leaders perform four key roles in reinforcing academic optimism: professional mentors, team builders, learning facilitators, and performance navigators.