When Teacher Preparation Programs Look Alike: Variability, Accountability, and the Limits of Program Differentiation

Research on teacher preparation programs (TPPs) continues to debate the extent to which program quality meaningfully shapes teacher effectiveness. While early evidence from high-income contexts documented nontrivial differences across programs, more recent studies suggest that most variation in teacher effectiveness occurs within rather than between programs. Using national administrative data from Chile and a three-level value-added model linking students, teachers, and preparation programs, this study estimates the share of variance in student achievement attributable to TPPs. Focusing on novice mathematics teachers linked to the only cohort with available lagged test scores (students assessed in 2015 and 2017), we find that TPPs account for approximately 1% of the total variance in student outcomes, while substantially more variation occurs within programs across teachers. Rather than interpreting this limited differentiation as evidence of uniformly strong preparation, we discuss how these patterns are consistent with institutional convergence and bounded instructional learning in a highly regulated system. The study contributes new empirical evidence from Latin America and offers a theoretically grounded interpretation of how accountability regimes may shape the distribution—rather than the overall level—of teacher effectiveness across preparation programs.