Abstract
This study delves into the efficacy of the reflective portfolio in the metacognitive domain within the context of the Master's in Secondary Teaching. It places particular emphasis on the impact of prior academic training in different specialties (scientific vs. humanities) on metacognitive skills development. The research employs a mixed-methods approach, analyzing portfolios from various academic specialties, developed in practicum subject, to ascertain differences in metacognitive competencies of teaching competencies. The main findings reveal that while students generally demonstrate a basic level of success in describing learning situations, there is a notable deficiency in deeper analytical skills and self-improvement strategies, especially among science students compared to their humanities counterparts. This suggests that initial training and educational background significantly influence the development of these competencies. The study concludes that there is a pressing need for more focused and robust training in metacognitive skills across different educational disciplines. Furthermore, it highlights the necessity for educational strategies that effectively address these variations, aligning teaching and learning processes with the principles of quality and sustainable education as envisioned in Agenda 2030. The insights gained are crucial for the development of more effective and comprehensive teacher education programs.