Unpacking Treatment Effect Heterogeneity in a Large-Scale Dropout-Prevention Experiment

August 2026

Timely high school completion is a critical step in successful transitions to post-secondary schooling and the labor market. This randomized controlled trial, deployed in two urban, disadvantaged school districts, tests the effectiveness of a mature and comprehensive student-support program on an unusually large scale (n=2,528). While overall effects on graduation rates are small and statistically insignificant, exploratory analyses reveal notable variation by site and over time, mirroring heterogeneity in treatment timing and program implementation. These findings highlight the challenges of scaling interventions and raise concerns about generalizing results from small-scale, single-site evaluations.

Keywords

high school graduation, dropout

Education level

K-12 Education

Topics

Out-of-School and Alternative Education