<![CDATA[Mathematics instruction in the Building Modeling and Information Design program requires students not only to master trigonometric concepts but also to develop reasoning literacy for interpreting building construction models within authentic vocational contexts. However, many vocational high school students continue to experience difficulties in connecting abstract trigonometric concepts with practical construction tasks. Although previous studies have investigated trigonometric conceptual understanding and Teaching Factory implementation, limited research has examined the integration of trigonometric conceptual understanding and building construction reasoning literacy within Teaching Factory-based mathematics learning. This study aimed to examine students' trigonometric conceptual understanding and their reasoning literacy regarding building construction models during the implementation of Teaching Factory-based mathematics learning. A descriptive qualitative survey design was employed involving 40 tenth-grade students enrolled in the Building Modeling and Information Design program. Data were collected through a trigonometric concept understanding test, a building construction reasoning literacy questionnaire, and semi-structured interviews, and were analyzed using descriptive qualitative techniques. The findings revealed that 45% of the students demonstrated a moderate level of trigonometric conceptual understanding, 40% achieved a high level, and 15% were classified in the low category. Similarly, the majority of students exhibited a moderate level of reasoning literacy regarding building construction models, indicating that conceptual understanding and reasoning literacy developed at varying levels within the Teaching Factory learning environment. These findings demonstrate that Teaching Factory-based mathematics learning provides a meaningful vocational context for strengthening the relationship between trigonometric conceptual understanding and reasoning literacy, thereby supporting the application of mathematics in authentic building construction tasks.]]>
