The Achievement Gap Initiative at Harvard University, via a kind reader:

In early 2009, the Achievement Gap Initiative (AGI) at Harvard University identified fifteen high schools with unusually strong evidence of student learning as measured by gains on standardized state exams. The schools had improved over a period of years. Most were racially and socioeconomically diverse. The AGI invited leaders of the identified schools to a two-day conference in June of 2009 to explain how their schools achieved such outstanding results.1 This report, How High Schools Become Exemplary, reviews and summarizes the presentations. The featured schools come from Massachusetts, Ohio, Illinois, Maryland, Texas, and Washington, DC. Each chapter here details how leaders engaged other adults in successful efforts to improve learning outcomes. The central theme is that schools improved performance by striving relentlessly to improve instruction.
Located at the boundary between adolescence and adulthood, high schools are critically important institutions. Unfortunately, they are the most stubborn part of the K-12 system to reform–the most impervious to change.2 In his recent book, So Much Reform, So Little Change, Charles Payne discusses the difficulty of reforming elementary schools and then comments that “The problems of elementary schools are exacerbated in high schools.”3 High schools tend to be fragmented organizations in which order is sometimes challenging to maintain and where responsibility for improving instruction resides mainly in isolated academic departments and classrooms. Principals are often distracted by crises. Many defer routinely to the subject-matter expertise of department leaders, seldom interfering with how departments monitor, evaluate, or attempt to improve teaching and learning.