California, a pioneer in school-based accountability, established the Academic Performance Index (API) in 1999, encompassing subjects and graduation rates. With the move past No Child Left Behind (NCLB), the state aims to enhance the API by embracing student growth, college readiness, and broader academic and social objectives. A RAND study identified additional measures adopted by 20 states, expanding beyond NCLB requirements, including student performance in extra subjects, growth over time, performance indices, and college readiness indicators. Emerging measures cover safe school environments, graduation risk, and interim assessments. RAND suggests customized local indicators, aligned incentives, supportive teaching structures, local validation studies, and collaborative statewide systems to foster comprehensive data collection and decision-making. As the Common Core assessments approach, the paradigm shifts towards redefining student achievement measurement, urging a holistic approach to data collection to inform stakeholders effectively.