In this action research work, I analyze the theory-practice integration in teacher preparation within the context of a science and technology (S&T) education teaching methodology course aimed at future elementary teachers. The course was designed, developed and evaluated taking into account this relationship as one of its axes. The results reveal that the proposal favors progress in theory-practice integration and stimulates the students' reflection and research. By means of a written report and an oral presentation, the students communicated their reflections on S&T teaching in the context of their concomitant professional practice. They also collected and presented resources and activities they found useful for teaching, practiced the use of certain educational S&T kits, and looked for and shared S&T pieces of news from different mass media. They additionally conducted a school learning project simulation and reflected on it. Besides, they prepared three written essays about theoretical-practical assigned readings and discussed them. In this paper, I refer to achievements and difficulties that emerged during the process, relating them to other research findings in the area and to theoretical considerations. Finally, I make proposals for further efforts in this field.