Since the year 2000, the population of people of color and of poor families in the suburbs has been rapidly increasing, making these areas far more diverse than they were a generation ago. Along with the increase in diversity has come re-segregation, leaving some schools with very high concentrations of low-income students and students of color, while others remain mostly white. These re-segregated schools are often not well-prepared to deal with the issues their students face. In addition, they are often subject to strict accountability demands that focus on improving test scores. These...