Sometimes called "exam schools," academically selective institutions have long been a part of the American secondary-education landscape. The schools are diverse in origin and purpose. No single catalyst describes why or how they began as or morphed into academically selective institutions. A number of them were products of the country's efforts to desegregate--and integrate--its public-education system, prompted by court orders, civil rights enforcers and activists, or federal "magnet school" dollars. Exam schools are sometimes controversial because "selectivity" is hard to reconcile with the mission of "public" education. Even school-choice advocates typically assert that, while families should be free to choose their children's schools, schools have no business selecting their pupils. Other people are troubled by reports of insufficient "diversity" among the youngsters admitted to such schools. With such criticisms in mind, the authors set out to explore this unique and little-understood sector of the education landscape.