A recent meta-analysis by Lynch and colleagues examined the effectiveness of professional development (Professional Development) interventions for mathematics and science teachers in grades PK-12. Analyzing 200 effect sizes for teacher outcomes and 126 effect sizes for student achievement from 46 experimental studies published from 2001 to 2024, the authors investigated how PD programs affect teachers’ knowledge and classroom instruction, and whether these changes translate into improved student learning.
The authors employed Hedges’s g as the effect size metric, using randomized controlled trial designs to ensure causal inference. PD interventions were categorized by their focus areas: improving teacher knowledge (content knowledge and pedagogical content knowledge), content-specific and content-general instructional strategies, and content-specific formative assessment. The researchers also examined contextual factors such as intervention duration, inclusion of curriculum materials, and school demographics.
The results revealed a significant positive impact of PD on teacher outcomes (pooled average: +0.52 SD). Specifically, teacher knowledge improved by +0.52 SD and classroom instruction by +0.49 SD. Importantly, programs with larger impacts on teacher outcomes also demonstrated significantly larger effects on student achievement. A 1 SD improvement in teacher-level outcomes was associated with a +0.18 SD gain in student achievement. Notably, improvements in classroom instruction showed a stronger link to student learning (+0.24 SD) than knowledge gains (+0.08 SD, not statistically significant). PD programs explicitly focusing on teacher knowledge development (effect size difference: +0.18 SD) and content-specific formative assessment (+0.27 SD) showed significantly stronger impacts on classroom instruction. Interestingly, intervention duration and the inclusion of curriculum materials did not significantly moderate outcomes.
The findings underscore that the quality and specific focus of professional development matter more than duration. Schools should prioritize PD programs that explicitly target both teacher knowledge and instructional practices, particularly emphasizing formative assessment strategies. The strong link between improved instruction and student achievement validates investments in high-quality professional development as a lever for enhancing educational outcomes in mathematics and science.
Source (Open Access): Lynch, K., Gonzalez, K., Hill, H., & Merritt, R. (2025). A meta-analysis of the experimental evidence linking mathematics and science professional development interventions to teacher knowledge, classroom instruction, and student achievement. AERA Open, 11, 23328584251335302.https://doi.org/10.1177/23328584251335302