The National Assessment of Educational Progress (NAEP) created a new measure of socioeconomic status for the 2024 exams. This is a welcome addition, and a better measure of student economic status has proven revealing, specifically regarding charter school performance. Shifting eligibility criteria made the reliability of the old standby, free and reduced-price lunch, questionable over time. The new socioeconomic status variables incorporate surveyed measures of the number of books in the home and parental education into a new measure. Charter schools have succeeded in large part in their core goal of improving the academic achievement of disadvantaged students.
A few caveats before jumping in: we have no trend data yet. Obviously, not all states have charter schools, and even fewer have charter sectors large enough to report NAEP achievement for charter subgroups.
The COVID-19 shutdowns impacted all these scores. Finally, NAEP is given to representative samples of students across states, so subsamples (low-socioeconomic status students) of subsamples (charter schools) can have large standard errors, which you can think of as the plus/minus that goes along with polling. This means both the red and the blue lines can be either too big or too small, or both at the same time.
Finally, differences may or may not reflect faster rates of learning by sector as it is not possible to control for all student differences with snapshots of achievement. Random assignment studies can (and have) shown positive academic impacts of charter school attendance, whereas NAEP data should be seen as merely suggestive. We are peering through a glass darkly, and as such I’ll try to bring in some other data along the way.
Having said all of that, with a few exceptions, the red-colored charter columns tend to be larger than the accompanying blue district columns. Just for some perspective, the difference between the nationwide “Basic or Better” number of 43% for charter schools as compared to 36% for district schools is statistically significant, meaning that it is unlikely to have been caused by chance.
Some of the red columns are much larger than their corresponding blue columns. For example, in the District of Columbia, low socioeconomic status charter school students hit the “Basic or Better” threshold at more than twice the rate as their district peers. This is no mean feat, especially since Patrick Wolf and his coauthors found that the District of Columbia Public Schools spent $4,245 more per pupil than DC charter schools in 2019-20. The Stanford Educational Opportunity Project also shows a faster rate of academic growth for DC charters between 2008 and 2019, which is at least directionally similar.
Should we take 64% of low socioeconomic status students in New York charter schools at face value? Perhaps so. CREDO’s analysis of charter performance found New York City had some of the highest performing charters in the nation. Using a matching research strategy, the researchers found that New York City charter students received the equivalent of 80 days of extra math instruction compared to their district-matched sample.
Obviously, what you should do with a sector of school that is crushing the academic ball with highly disadvantaged students is to cap the total number you can have, which is what New York’s highly ethical lawmaking class has done. They can’t get enough of New Yorkers becoming Floridians.
The same crosstab procedure for the eighth grade reading exam produces information for fewer states, as seen in Figure 2 below.
The national difference between charters and districts again registers as statistically significant. I would test the state differences, but the NAEP website moves at a glacial pace, and we have deadlines to meet here at your favorite edublog. More to come, but for now let’s just note that charter schools have largely succeeded on average in producing better academic outcomes with significantly fewer resources.
