<![CDATA[Background: Cambodian STEM educators require professional learning that supports inquiry-based teaching, scientific reasoning, and the classroom application of the Next Generation Science Standards (NGSS) and Claim-Evidence-Reasoning (CER) framework. Aims: This study examined changes in educators' pedagogical knowledge, scientific reasoning, and instructional competencies following an integrated professional development program. Methods: A quantitative single-group pre-test-post-test design was employed with 30 Cambodian STEM educators. Participants completed a two-day workshop structured through six Cognitive Apprenticeship processes: modeling, coaching, scaffolding, articulation, reflection, and exploration. They also engaged in authentic engineering design activities using creative circuits aligned with NGSS and CER. Data were collected before and after the workshop using a 14-item questionnaire rated on a five-point Likert scale. Descriptive statistics (means and standard deviations) were used to analyze the responses. Results: Mean scores increased across all 14 items, with the overall mean rising from 1.98 at pre-test to 3.62 at post-test. Higher post-test ratings were observed for understanding NGSS three-dimensional learning, constructing CER-based scientific explanations, designing NGSS-aligned lessons, and applying science and engineering practices. Conclusion: The findings indicate that participation in the workshop was associated with improved self-reported knowledge and pedagogical competencies. However, because the study did not include a comparison group, the observed changes cannot be attributed solely to the intervention. The integrated approach offers a promising model for future STEM teacher professional development in Cambodia, although further research using controlled designs and classroom-based outcome measures is needed.]]>
