This qualitative phenomenological study explored the lived experiences of seven public school teachers in the Philippines during the implementation of the National Mathematics Program (NMP). Grounded in educational reform theories and curriculum implementation models, the study explored how teachers in Cebu City and the Province experienced the implementation of the National Mathematics Program (NMP). Data were collected through in-depth interviews and analyzed using thematic analysis to identify recurring patterns and key themes. Researchers identified significant challenges, including a lack of subject-specific expertise, inadequate resources, and limited support. These challenges hindered teachers' ability to align classroom instruction with NMP standards. The study emphasized the crucial need for targeted professional development to enhance teachers' understanding and application of NMP concepts. Furthermore, providing teachers with the necessary resources and institutional support is essential for successful program adaptation. Ultimately, the study underscores that addressing these challenges is critical for improving student learning outcomes and ensuring the success of educational reforms like the NMP.