In this intervention-based action research study, we first conducted interviews with 20 Colombian pre-service language teachers. The pre-service teachers' perspectives indicated their awareness of the multidimensional role of the teacher and the complexity of the teaching profession, and we identified their self-perceived competencies and areas where they desired improvement as future language teachers. The findings informed our design of co-curricular activities that addressed pre-service teachers' concerns. Next, we implemented and evaluated the co-curricular activities which helped pre-service teachers develop new understandings. The study sheds light on the crucial role of intervention-based action research and co-curricular activities in teacher preparation. We discuss implications for teacher educators as critical agents of change in teacher preparation and the teaching profession.