<![CDATA[The integration of Science, Technology, Engineering, and Mathematics (STEM) into science education has become an effective approach to fostering students' higher-order thinking and science process skills. However, the limited availability of interactive learning media for renewable energy topics, particularly mini hydropower systems, remains a challenge in high school science instruction. This study aimed to develop a STEM-based Mini Hydropower Education Kit on renewable energy materials and evaluate its validity, practicality, and effectiveness in improving high school students' science process skills. This research employed the Research and Development (R&D) method using the ADDIE model, consisting of Analysis, Design, Development, Implementation, and Evaluation stages. The developed education kit was validated by experts in physics education, learning media, and instructional design. The implementation involved high school students who participated in STEM-oriented learning activities using the developed kit. Data were collected through expert validation sheets, student and teacher response questionnaires, observation sheets, and science process skills tests administered before and after the intervention. The findings indicated that the developed education kit achieved a very high level of validity and practicality based on expert assessments and user responses. Furthermore, the implementation of the STEM-based Mini Hydropower Education Kit significantly improved students' science process skills, including observing, formulating hypotheses, conducting experiments, interpreting data, and drawing conclusions. The improvement was reflected in higher post-test scores compared to pre-test results and supported by positive student engagement during learning activities. Therefore, the developed education kit can serve as an effective instructional medium for renewable energy education while promoting meaningful STEM learning and enhancing students' science process skills in secondary education.]]>
