We present a reconceptualized framework for opportunity to learn (OTL) in school mathematics that builds on previous conceptualizations of OTL and includes features related to both quantity (i.e., time) and quality. Our framework draws on existing literature and on our own observational research of mathematics teaching practices. Through the presentation of two teaching vignettes, we highlight key features of mathematics instruction that seem to differentiate students' OTL. These features are nested under four key dimensions in our OTL framework: "the teacher's mathematical knowledge for teaching" ("MKT"), how "time" is utilized in the lesson, the mathematical "tasks" implemented with students, and the nature of the mathematical "talk" in which students engage. We discuss implications for the use of the framework as well as its shortcomings.