Mathematics Curriculum Effects on Student Achievement in California

1,878 California elementary schools

California elementary schools in the pre-Common-Core textbook market.

School-level panel/matching design comparing adoption of four elementary mathematics textbooks on state test scores. Non-experimental: adoption is a district choice, so unobserved district characteristics are the residual threat.

A conventional, practice-heavy textbook beat its rivals by ~0.05-0.08 SD at essentially zero marginal cost — 'big bang for a few bucks'. The result is era-dependent: it shrank to ~nothing after Common Core homogenised the market.

Non-experimental and school-level; student composition is held roughly constant by the within-school comparison, but curriculum choice is not random.

Converges with the Agodini RCT and with the Indiana matching study on structured/practice-heavy texts. The same authors' 2020 multi-state study found the differences largely gone in the post-Common-Core market.