In the Zone: From cradle to college to community building
You can also download a PDF of a recent article about the efficacy of the HCZ: “Are High-Quality Schools Enough to Close the Achievement Gap? Evidence from a Bold Social Experiment in Harlem.”
Authored by Will Dobbie and Roland G. Fryer, Jr. in April 2009, the abstract reads:
Harlem Children’s Zone® (HCZ) is arguably the most ambitious social experiment to alleviate poverty of our time. We provide the first empirical test of the causal impact of HCZ on educational outcomes, with an eye toward informing the long-standing debate whether schools alone can eliminate the achievement gap or whether the issues that poor children bring to school are too much for educators to overcome.
We implement two identification strategies. First, we exploit the fact that HCZ charter schools are required to select students by lottery when the demand for slots exceeds supply. Second, we use the interaction between a student’s home address and cohort year as an instrumental variable. Both approaches lead us to the same story: Harlem Children’s Zone is enormously effective at increasing the achievement of the poorest minority children.
Taken at face value, the effects in middle school are enough to reverse the black-white achievement gap in mathematics and reduce it in English Language Arts. The effects in elementary school close the racial achievement gap in both subjects. Harlem Gems and The Baby College®, the only two community programs in HCZ that keep detailed administrative data, show mixed success.
We conclude by presenting three pieces of evidence that high-quality schools or high-quality schools coupled with community investments generate the achievement gains. Community investments alone cannot explain the results.