Success for All is the most extensively researched of all comprehensive reform models for Title I elementary schools. It incorporates scientifically based principles of reading, cooperative learning, professional development, tutoring, and family support. Arkansas elementary schools using the Success for All reading program continued to make outstanding gains on the Arkansas Benchmark Exams in reading and writing literacy. From 2002 to 2004, Success for All schools gained 19.6 percentage points in fourth graders scoring at or above "proficient." Other Arkansas schools gained 11.0 percentage points.