Although much has been written about the potential benefits of effective data use in schools, considerably less attention has been paid to how schools make sense of the data generated from performance-based accountability measures. This article explores schools’ usage of state test data, the intensity of data use, and the perceived utility of state test data. Our findings uncover nuanced differences in school data use and reveal a key disconnect in the assumptions of performance-based accountability systems, wherein schools may faithfully use state data to inform improvement efforts while fundamentally questioning the validity of the data itself.