We develop a new framework for identifying at-risk students in public schools. Our framework has two fundamental advantages over "status quo" systems: (1) it is based on a clear definition of what it means for a student to be at risk and (2) it leverages states' rich administrative data systems to produce more informative risk measures. Our framework is more effective than common alternatives at identifying students who are at risk of low academic performance and we use policy simulations to show that it can be used to target resources toward these students more efficiently. It also offers several other benefits relative to "status quo" systems. We provide an alternative approach to risk measurement that states can use to inform funding, accountability, and other policies, rather than continuing to rely on broad categories tied to the nebulous concept of "disadvantage."