In their recent study of the impact of high-"Value-Added" teachers, Raj Chetty and his colleagues find that a student who was able to substitute an extremely weak teacher -- one who ranked in the bottom 5% of the distribution of all teachers -- for one substantially better, would reap benefits into adulthood. Specifically, at age 28, that lucky student would earn $182 more per year than he would have with the bad teacher. While this is a very small amount of money -- indeed, it represents not quite a percentage point increase over the baseline of $20,912, over the person's life, it would add up somewhat. And when the entire class's benefits are taken into account, that number might rise as high as $250,000 for the cohort.
The researchers acknowledge that achieving a full standard deviation increase in teacher Value Added is no small feat, however, noting the weak evidence of the efficacy of bonuses for high-VA teachers. As such, it is worth considering the benefits of other potential education interventions. This isn't easy -- few studies provide estimates of both benefits and costs. Indeed, Chetty and colleagues can't calculate costs here. But one rigorous study provides both of these metrics for comparison: Arthur Reynolds, Judy Temple and colleagues' Age-28 study of graduates of Chicago Child Parent Centers, a high-quality pre-k program set in the Chicago public schools.
Students who participated as four-year-olds have been tracked for the past 25 years and data collected from multiple sources, so the researchers were able to estimate increases in their adult earnings. These turn out to be between $786 (average 2004-2007) and $932 (unadjusted 2007) per student annually, four to five times the impact of the substitution of terrible for average teachers. Given Chetty et al's contention that a $182 increase merits policymaker attention, pre-k programs like the Chicago Child-Parent Centers should command it.
Moreover, we know exactly how to implement high-quality pre-k programs. Not only are the Chicago Child-Parent Centers up and running, rigorous evaluations of pre-k programs in Arkansas, Michigan, New Jersey, New Mexico, Oklahoma, South Carolina, and West Virginia suggest that, based on initial indicators, they are poised to deliver substantial societal returns.
Chetty and his colleagues suggest that, given the worth of a great teacher, parents might collectively pool their own money -- $4,600 per parent, totally out of reach for virtually all the families of the students studied -- to retain him/her. It is both feasible and cost-effective, however, for society to invest the $5,000 to improve the poor-quality early education too many low-income children currently receive. States and districts can even accomplish this without burdening the taxpayer, by re-allocating their Title I funding. This would provide at-risk children access to programs like Chicago's -- at about $10,000 per child -- and reap four times the benefits. A rare education no-brainer.