The LASER (Leadership and Assistance for Science Education Reform) model, developed by the Smithsonian Science Education Center (SSEC), is a systemic approach to transforming science education consisting of five elements: a research-based, inquiry-driven science curriculum; differentiated professional development; administrative and community support; materials support; and assessment. These elements, when planned around a shared vision for science, form the infrastructure to sustain student-centered learning and teaching. Evaluators from the Center for Research in Educational Policy (CREP) at the University of Memphis studied approximately 60,000 students attending public schools (urban, rural, and suburban) in (1) the Houston Independent School District (HISD); (2) eight school districts in northern New Mexico; and (3) seven school districts in North Carolina. CREP employed a matched-pair randomized controlled trial (RCT) using a comparison group design. CREP investigated whether students in schools implementing the LASER model during a three-year period outperformed students who were not exposed to LASER during the same time period. [Additional funders for the SSEC LASER i3 study include the JP Morgan--National Philanthropy Trust and Teresa Bergeson.]