From the abstract: "This article describes Literacy Data-Driven Decisions (L3D), which is a preschool literacy program, grounded in DDDM that was developed across two federally-funded research projects. The first project investigated different components within an MTSS model and created a DDDM tool called the Tune-Up Checklist. The TUC is a self-reflection tool that guides instructional implementation. The second project expanded the TUC to include fidelity of implementation checklists and created L3D.