This research explores the understanding of English teachers at SMP Negeri 1 Kolaka in developing teaching modules based on the Kurikulum Merdeka, focusing on the processes and challenges involved. Employing a qualitative approach with a case study method, data were gathered through semi-structured in-depth interviews and document analysis (teaching modules) from three English teachers who participated in Guru Penggerak training. Thematic analysis was applied to identify patterns across interview transcripts and documents. The findings reveal two major themes: (1) English teachers' understanding, encompassing four sub-themes conceptual understanding of teaching modules, the development process, implementation, and evaluation and improvement; and (2) difficulties faced, encompassing seven sub-themes adjusting teaching modules with the Alur Tujuan Pembelajaran (ATP), conducting needs analysis, using appropriate operational terms, determining module components, aligning Profil Pelajar Pancasila (P3) elements with Tujuan Pembelajaran (TP), flexibility in lesson plan implementation, and challenges in technology integration. While teachers demonstrated good conceptual understanding and developed modules that met minimum components, challenges remain in needs analysis, operational verb selection, P3-TP alignment, and technology use. Further training and support, particularly in technology integration and needs analysis, are recommended.