Achievement Effects of Four Early Elementary Math Curricula (IES cluster RCT)
Agodini, R., Harris, B., Seftor, N., Remillard, J., & Thomas, M. (Mathematica for IES) · 2013
grade Brctindependentmixednumbers spot-checked
Sample
111 schools randomized; 58 schools (2,045 students) in the 2-year analysis
Population
Grades 1-2, 12 districts, 10 states; Title I-heavy volunteer sample.
Design
The only multi-curriculum RCT in US elementary math: schools randomized to Saxon (scripted), Math Expressions (blended), Investigations (constructivist), or SFAW/enVision (basal). Independent ECLS-K outcome. Caveats: 2-year result from the 58 voluntarily-continuing schools; Saxon grade-2 teachers spent ~1 extra hr/week on math.
Key findings
The cleanest causal evidence in the math wars: the only stable loser across two years is the most strongly constructivist, minimal-guidance curriculum (Investigations), trailing ALL three rivals by 0.22 SD on an independent test. The winner set is heterogeneous (scripted, blended, conventional) — the result indicts the low-guidance pole rather than crowning scripting.
Genetic confound
Random assignment removes selection; curriculum effects on domain skills.
Replication notes
Numbers verified from NCEE 2013-4019. Direction converges with Indiana matching (Bhatt-Koedel); post-CCSS multi-state data (Blazar 2020) show curriculum differences largely vanished — era-dependent.
DOI / URL
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| After 2 years: each rival vs Investigations | SD | +0.22 (69.4 vs 65.5, SD=18; ~9 percentiles); winners indistinguishable from each other | standardized | end of year 2 | active-alternative | end-of-treatment | domain-skill |
| Year 1: Math Expressions/Saxon vs Investigations | SD | ~+0.15-0.18 (first cohort up to +0.24-0.30) | standardized | end of year 1 | active-alternative | end-of-treatment | domain-skill |
| Curriculum switching (SFAW year1 -> Saxon year2) | SD | +0.35 (significant); other switches null | standardized | end of year 2 | active-alternative | end-of-treatment | domain-skill |
Cited by
- Curriculum choice as a school-level levermixedconf: highgc: low
- Explicit vs reform/constructivist math instructionmoderate supportconf: highgc: low
- Math curriculum choice — how much does the textbook matter?mixedconf: highgc: low