In December of 1993, Bill Clinton remarked that figuring out how to consistently replicate great schools was the central education policy problem of our age. A generation later, it still is.

As someone obsessed with solving that problem, I wanted to know how well our current strategies for achieving it are working. One strategy in particular has attracted the bulk of the funding and attention over the past decade: philanthropists teaming up with what they consider to be the best networks of charter schools, and funding their growth. To find out how well they’ve been picking the winners, I compared the total amount of grant funding received by each of 68 California charter school networks over the past 8 years to the academic performance of those networks. The study is available here.

The correlation between grant funding and performance on the California Standards Tests turns out to be negligible (0.1). In fact, it’s half the size of the correlation between performance and the length of the networks’ names. As a check on those findings, I also ran the numbers on AP test performance. Those results are slightly worse: though the correlations are also negligible in magnitude, they’re actually negative in sign—more grant funding is associated with minutely worse AP performance.

In a nutshell, it’s as if philanthropists have been doling out funding to charter school networks by the same random lottery process by which oversubscribed charters are obliged to accept new students. While this will of course be viewed as a great disappointment by a great many people, it is better to have this information than to continue to labor in ignorance. There are places where excellence in education does routinely scale-up, and documenting them is the subject of my next project.…