Learning biology on the human motion system material often presents challenges due to the complex and abstract nature of the material. This study aims to improve student learning outcomes by applying the Discovery Learning learning model assisted by video media in class X SCIENCE SMA Negeri 2 Tondano. This research is a Class Action Research which was carried out in two cycles using a collaborative reflective approach. Each cycle consists of planning, action, observation, and reflection stages, with data collection through observation, evaluation tests, interviews, and field notes. The results in the first cycle showed that the average student score only reached 53.4 with a classical completeness rate of 32%. In cycle II, after improvements based on reflection in cycle I, learning outcomes increased significantly, with an average of 85.3 and a completeness rate of 100%. These findings show that integrating video media in discovery-based learning effectively improves students' understanding of hard-to-visualize biological concepts. Audio-visual media help students relate visual information to authentic experiences, while Discovery Learning encourages active and exploratory engagement of students in the learning process. This research contributes to the science education literature by showing that technology-based and participatory learning strategies can answer the challenges of biology learning in secondary schools. Implicitly, teachers are encouraged to adopt a similar approach to create active, engaging, and meaningful learning.