Indonesian Teachers' Conceptual Understandings of Newtonian Mechanics and Classroom Teaching Practices

Physics teachers play a crucial role in developing students' conceptual understanding of physics concepts. This study examines Indonesian physics teachers' understanding of Newtonian mechanics and its implications for teaching practices. We used the Force Concept Inventory (FCI) and semi-structured interviews to analyze participant responses to mechanics-related questions. The findings reveal that teachers with a strong grasp of Newtonian mechanics tend to implement guided-constructivist instructions (GCI) to foster students' engagement and deeper learning. In contrast, those with weak or non-Newtonian understandings rely on Content-Centered Instructions (CCI) and hesitate to adopt a student-centered approach, citing reasons such as time constraints, rigid instructional goals, and a lack of students' motivation. Our findings highlight the urgent need for targeted professional development programs that enhance teachers' conceptual understanding of Newtonian mechanics.