Back on Track? Academic Screening, Cohort Sorting, and Achievement in NYC Middle Schools

• In Event: School Choice, Screening, and Stratification: Evidence on Enrollment and Composition

Abstract

Academic screening—admitting students to public schools based on prior achievement—is a widely used but contested tool in urban school choice systems. Proponents argue that grouping students by preparation level enables more targeted instruction and promotes efficiency gains in student learning. Critics contend that screening entrenches racial and socioeconomic inequalities by systematically favoring students from advantaged backgrounds, and instead advocate for policies that promote equal access, such as lottery-based admissions. Yet despite the policy salience of this debate, causal evidence on its consequences outside elite exam school contexts is scarce. This paper provides causal evidence on how academic screening affects cohort composition, application behavior, and subsequent student achievement in New York City public middle schools. I exploit a 2023 reform that reversed a 2022 mandate that all schools use a lottery to determine admission priority. In response, 52 middle school programs across 21 sub-districts transitioned from lottery-based to standardized academic screening. I use a difference-in-differences design to estimate the effects of screening on application behavior, admitted cohort composition, and 6th-grade academic outcomes at the program level. I link administrative data on approximately 60,000 annual middle school applicants to student-level test scores, course grades, and demographic characteristics. Because each of NYC's 32 sub-districts operates as a largely self-contained middle school market, variation in how many programs adopted screening across sub-districts translates directly into variation in overall market-level exposure to screening. I exploit this continuous variation—measured as the share of seats allocated via academic screening within each sub-district—in a difference-in-differences design to estimate the causal effect of screening intensity on aggregate sub-district outcomes. At the program level, screening substantially reshapes both who applies and who is admitted: treated programs admit cohorts with average prior achievement 0.44 standard deviations higher than previously, attract fewer applications from Hispanic and low-income students, and enroll a higher share of Asian students. Students in screened programs exhibit higher 6th-grade math scores, with gains concentrated among students above the 40th achievement percentile when they were in 5th grade. At the district level, I find minimal effects of screening intensity on aggregate student achievement and measures of racial and economic segregation. These findings suggest that while screening reshapes access and demographic composition within programs, its aggregate consequences for student achievement and segregation are more limited than critics contend.

Author

• Jerray Chang, Boston University
  Presenting Author