
Roland Fryer (second from left) found that most of the HCZ's success in student performance can be chalked up to its charter schools, and not to the social programs championed by HCZ's founder, Geoffrey Canada (far right).
A foundational belief at the Harlem Children’s Zone is that erasing the achievement gap between black and white kids requires a comprehensive, resource-intensive approach. The idea is that middle-class white kids don’t just have better schools, but the kind of home lives that lend themselves to better school performance. HCZ is essentially trying to fill in all those gaps with a robust array of social services. More health screenings. More early childhood programs for parents and children. Students at HCZ’s charters have longer school days and shorter summers.
Both lottery and instrumental variable identification strategies suggest that the effects of attending an HCZ middle school are enough to close the black-white achievement gap in mathematics. The effects in elementary school are large enough to close the racial achievement gap in both mathematics and ELA. We conclude with evidence that suggests high-quality schools are enough to significantly increase academic achievement among the poor. Community programs appear neither necessary nor sufficient.
In a weird way, this might actually help propagate some of HCZ’s principles. The big dilemma with their kitchen-sink approach, if proven successful (and this Harvard study certainly won’t be the last word on whether that is or isn’t the case) is that it would be hard, if not impossible, to scale up to a whole district. Very few cities would have the political will to do so, and few cities that had the will would have the means. (HCZ’s operating budget in 2010: $84 million.) Nor would they have Geoffrey Canada, HCZ’s influential leader, to guide their implementation. But they could replicate, somewhat, the way HCZ’s schools themselves function. (The Obama administration’s efforts to copy the HCZ neighborhood-wide model have been relatively small bore.)
But there are plenty of arguments for HCZ to keep going ahead with all of their social services, scalability or no. That asthma screening program has no effect on classroom performance, but it’s still a worthwhile endeavor. (The CDC took an early look at the asthma initiative a few years ago — Harlem’s asthma rate is five times the national average — and found that the rate of school absences and emergency or unscheduled doctor’s visits dropped dramatically for kids enrolled in the asthma program.) You’d think that less absences would mean better school performance, but even if it doesn’t, there are still a bunch of kids in Harlem who are much less sick.
I’m ambivalent about HCZ’s profile in national policymaking relative to its modest successes, but that seems worthy of some applause.