The long-term goal of this model demonstration project is to contribute empirical evidence on the effectiveness of a system of instructional practices for supporting the algebra readiness of middle-school students with specific learning disabilities in mathematics. In this system, three theoretical and practical frameworks intersect, including (1) the process of data-based individualization (DBI), (2) the principles of explicit and systematic instruction, and (3) key components of algebra readiness. Individually, each framework has an evidence base for improving outcomes for students with disabilities. This project, however, seeks to amplify previous evidence of effectiveness by integrating these frameworks into a coordinated system of professional learning and practice that focuses on fidelity of implementation and sustainability. DBI integrates assessment and instructional design principles to create individualized, responsive intervention for students with persistent learning needs.