Are Middle Schools More Effective?
利用定量证据，比较初中体系与中学体系对学生按时高中毕业率的影响，发现中学体系反而使毕业率下降1-3%。
While nearly half of all school districts have adopted middle schools, there is little quantitative evidence of the efficacy of this educational structure. We estimate the impact of moving from a junior high school system, where students stay in elementary school longer, to a middle school system for on-time high school completion. This is a particularly good outcome measure because middle school advocates argued that this new system would be especially helpful for lower achieving students. In contrast to the stated objective, we find that moving to a middle school system decreases on-time high school completion by approximately 1–3 percent.