This study analyzes how the resignification of school mathematical knowledge (SMK) is configured among in-service teachers within a professional development program oriented toward teacher empowerment. The program was designed and implemented, and two episodes related to algebraic and geometric thinking were analyzed. Methodologically, indicators were constructed based on the model of problematization of school mathematics in order to identify evidence of confrontation, resignification, and changes in the relationship with SMK. The results show that the resignification of SMK is configured as a cyclical, collective, and progressive process that articulates both epistemic and didactic dimensions across the experiential phase, classroom implementation phase, and reflective practice phase. The epistemic dimension emerges more strongly in the experiential phase, while the didactic dimension becomes consolidated in the subsequent phases. It is concluded that the resignification of SMK is not only a central mechanism for teacher empowerment, but also a constitutive element of the mathematics teaching profession.