This study describes and analyzes the impact on student learning and the learning environment of 55 schools in Broward, Palm Beach, and Miami-Dade school districts as they implemented the schoolwide action-research framework for school improvement. Interviews, observations, document review during site visits, school framework reports, surveys, school newsletters, focus groups, and training institutes were examined. Study groups of 6 to 12 educators were formed who received 6 to 9 days of training to implement the action-research process, as well as professional development in math, science, or reading content pedagogy. When using action research teachers continually observe students, collect data, and change practices to improve student learning and the learning environment. Teachers come to have a better understanding of why, when, and how students become better learners. Improvement is seen in problem-solving capabilities through repeated cycles of research. During a 3-year program, faculty members choose a focus area, collect and analyze data, study professional literature and best practices, and take action. Educators complete the cycle repeatedly pursuing improvement. Among the attributes of schools in the study with significant improvement were the presence of administrators at training and study-group sessions, the study goal being embedded in day-to-day work rather than as an extra task, and the focusing on a student learning goal early in the study. (Contains 15 references.) (RKJ)