The research score continues to run-up in favor of the old Gates education reform strategy of creating small schools of choice rather than the new Gates PLDD strategy of centrally determining what students should be taught (Common Core) and how teachers should be evaluated (Measuring Effective Teachers). When Tom Vander Ark led the Gates education effort, they had a winning strategy.
The new evidence comes from another paper that was presented at the Association for Education Finance and Policy conference. Two of my excellent students, Anna Jacob Egalite and Brian Kisida, received a data award from the Kingsbury Center to analyze the effect of school size on student achievement using NWEA test results. They used a student-fixed-effects research design to see if students improved or worsened their academic achievement when they switched to a school of a different size. And the results:
We found consistent negative effects of large school size on student math and reading achievement, especially in secondary schools that enroll more than 540 students. In grades 6-10, for example, math achievement declined by -.043 SD (standard deviation) and reading achievement declined by -.024 SD.
If a student moved from a largest quintile school in grades 6-10 to a school in the smallest quintile for those grades, we would expect a 6.4% of a standard deviation improvement in math performance. Of course, a student fixed effects study is not quite as strong methodologically as the random-assignment evaluation of small high schools in New York City, but it is pretty darn good. And this study has the advantage of using a large data base of more than 2 million students from across the country. It’s pretty clear that students would benefit significantly from a reduction on school size — especially junior high and high school students.