A Guide for the Perplexed — A Review of Rigorous Charter Research

Colin Hitt:

So you say charter schools don’t work. That’s an empirical claim. It needs to be backed up by evidence. Here’s a helpful guide to the most rigorous research available. Once you’ve tackled this material, you’ll be in position to prove your point.
As you probably know, the gold standard method of research in social science is called random assignment. Charter schools are particularly well-suited for random assignment evaluations, since they’re usually required by law to admit students by lottery. The lotteries are fair to families – that’s why they’re put in place. But they also allow researchers to make fair comparisons between students who win or lose lotteries to attend charter schools.
To date, nine studies lottery-based evaluations of charter schools have been released. Let’s go through them, starting with the earliest work.
The first random assignment study of charter schools was released in 2004 by Caroline Hoxby and Jonah Rockoff. It focused on Chicago International Charter School. After three years, charter students had significantly higher reading scores, equal to 3.3 to 4.2 points on 100-point rankings. Gains were even stronger for younger students.