Abstract. This study investigates the effects of open educational resource (OER) utilization, specifically revision, remix, and redistribution, on students' academic performance in science for the school year 2023- 2024. Using a descriptive-quantitative research design, data were collected from teacher respondents through a survey questionnaire. The results showed that teachers predominantly utilized OER for revision, with moderate engagement in remix and redistribution activities. Students' academic performance, measured by their general weighted average in science for the first quarter, was satisfactory, with a mean score of 83.73. The findings indicated that using OER for revision significantly enhanced students' academic performance while remixing and redistribution did not significantly impact student outcomes. Furthermore, no significant differences were found in the extent of OER utilization among teachers based on sex, educational attainment, years of teaching experience, or relevant training. These results highlight the need for targeted professional development programs that emphasize the effective use of OER in revising, remixing, and redistributing educational materials. Schools can foster more innovative and personalized student learning experiences by improving teachers' capacity to utilize OER fully. The study recommends that educational institutions ensure the availability and accessibility of high-quality OER, alongside ongoing support and training for teachers, to optimize their potential to improve student achievement. Ultimately, the findings suggest that strategic integration of OER into instructional practices can lead to enhanced educational outcomes and greater collaboration among educators.

Keywords: Open Educational Resources (OER); Revision; Remix; Redistribution; Science education.