<![CDATA[Mathematics learning at the elementary school level often faces obstacles in visualizing abstract concepts, especially in the material of plane figures. Students tend to have difficulty in connecting theoretical concepts with real objects in the surrounding environment. This study aims to develop a project-based learning module by integrating an ethnomathematics approach through the exploration of Riau Malay Traditional House ornaments. The use of traditional ornaments was chosen as a contextual medium because it is full of unique and authentic geometric patterns. The research method used is Research and Development (R&D) using the ADDIE development model which includes the stages of Analysis, Design, Development, Implementation, and Evaluation. Data collection was carried out through observations of traditional house ornaments, in-depth interviews with cultural experts and craftsmen, and validation by material and media experts before being implemented to 3rd grade elementary school students. The results of the study indicate that Riau Malay Traditional House ornaments, such as the Pucuk Rebung and Itik Pulang Petang motifs, contain very rich principles of plane geometry, including an understanding of triangles, trapezoids, parallelograms, and the concept of symmetry. The developed module has met high validity and practicality criteria. Furthermore, findings from the implementation phase indicate that students' active involvement in this cultural exploration project successfully increased their learning interest, facilitated their understanding of geometric concepts, and enhanced their spatial reasoning skills. Furthermore, this study demonstrates that the integration of local wisdom into the mathematics curriculum is not only effective as a pedagogical tool but also plays a crucial role in fostering students' love and pride for the identity and cultural heritage of Riau Malays from an early age]]>
