The goal of this study was to produce recommendations for states and school districts seeking a flexible, systematic approach to swift and significant transformation in schools (particularly high schools) deemed chronically under-performing under No Child Left Behind or state accountability systems. This research leads the authors to believe that turnaround of this kind is achievable, and furthermore, has the potential to open the door to more widespread dramatic education reform. The authors hope that the analysis, conclusions, and framework presented in this report will help educators, school reformers, and policy leaders across the country develop a new generation of turnaround strategies that carry, at the very least, the possibility of success. Appended are: (1) School Intervention to Date: Goals, Strategies, and Impact; and (2) References. (Contains 39 figures.) [For "The Turnaround Challenge: Why America's Best Opportunity to Dramatically Improve Student Achievement Lies in Our Worst-Performing Schools. Executive Summary," see ED538309. For "The Turnaround Challenge: Why America's Best Opportunity to Dramatically Improve Student Achievement Lies in Our Worst-Performing Schools. Supplement to the Main Report," see ED538300.]