A codesign professional development model for developing stem curriculum design competency in junior high school natural science teachers in Northern Vietnam

In the context of Vietnam’s competency-based education reform, this study addresses the gap between STEM policy mandates and teachers’ practical capacity. We evaluate a professional development model synthesizing the Research-Practice Partnership (RPP) framework and Co-design mechanisms. Using an explanatory sequential mixed-methods design, data were collected from 30 junior high school teachers via competency tests, interviews, and observations. Quantitative results showed a significant increase in overall STEM design competency, with mean scores rising from 5.75 ( SD = 1.24) to 8.09 ( S D = 0.54) on a 9-point scale ( Z =-4.786, p < 0.001, r = 0.618). Qualitatively, collaborative peer learning and iterative design drove this improvement. These mechanisms also fostered teacher agency, transforming participants from passive implementers into active curriculum designers. While limited by a small sample size, the study affirms the model’s effectiveness in cultivating professional autonomy. Future longitudinal research is recommended to assess the long-term impact on classroom implementation.