Thread by @douglasharris99

1/ Excited abt our latest @REACHCtrEd report on the effects of charter schools nationally: reachcentered.org/publications/d…. I did this with my PhD student Feng Chen. A thread on results…

2/ One contrib is studying system-wide outcomes, ie, a weighted avg of trad public schls (TPS) & charter results. This means: a) little worry abt self-selection of students into charters; & b) we capture net effects of various ways charters affect student outcomes, incl thru TPS

3/ In everything below, we compare districts w >10% enrollment share (ie “charter-heavy”) w zero-charter districts, in a “matched diff-in-diff” res design. Results are similar when we use diff methods (“fixed effects”). Lots of tests suggesting estimates reflect causal effects.

4/ This is the 3rd study to my knowledge to study charter effects on a national scale. We find, for example, that charter-heavy districts increased student math and reading scores by 0.15 and 0.08 standard deviations, respectively.

5/ This is one of a handful of studies to examine charter effects on HS grad rates. We find that these increase by 2-3 percentage points. (BTW, the policy brief provides an easy-to-read summary of all of this.)

6/ We also dig into specific mechanisms behind these effects. We find that charter schools locate near TPS that are somewhat lower-performing than avg & charters induce some low-perf TPS to close (which means students move to other, probably higher-performing, schools).

7/ The positive effects are concentrated in metro areas; no effects in non-metro. The positive effects also look generally similar across racial/ethnic groups & income levels.

8/ I mentioned there have been 2 other national studies on charters & you might have noticed that @educationgadfly put out a related analysis on the exact same day (truly a coincidence). The other is @CREDOatStanford. I can get into method differences if anyone wants.

9/ This also builds on other great work by #Nobel @metrics52 @dynarski @SarahCohodes @imbernomics @prof_parag @RonZimmer8 @BrianGill_edu & many others not on Twitter. Another shout out to my excellent student & co-author Feng Chen (who is on the job market, BTW).

10/ Lots of other great studies on school choice @REACHCtrEd to come. See also our other recent work on how states can do more to increase equity in school choice: reachcentered.org/publications/s…. If you made it this far, thanks for your patience.