Harder Course, Higher Score? Exploring the Heterogeneous Effects of Eighth-grade Algebra Enrollment on Average Math Achievement

Many empirical studies have provided evidence both supporting and opposing the practice of detracking. While some researchers have shown that high-achieving students from disadvantaged backgrounds can be disadvantaged by detracking, there has been limited research on how this within-school revolution may impact the achievement gap between schools. To address this gap, this study applies a propensity score-based method to hierarchical models and utilizes data from the Early Childhood Longitudinal Study—Kindergarten class of 1998–1999 (ECLS-K) in order to explore the causal inference of expanding algebra access. More specifically, it examines the average and heterogeneous effects of enrolling more eighth-grade students in algebra on school average achievement. The study finds, in conclusion, that enrolling all students in algebra has insignificant effect on school average test scores due to the heterogeneity of the effect. Only high-achieving schools benefit from this comprehensive detracking process, resulting in an increase in the achievement gap between schools. However, for schools that do not offer algebra, enrolling some students in algebra increases their average achievement without significant differences in the effects among different schools. These findings provide insights into how course offering policies should be implemented among schools.