This study explored learning which occurred when mature distance education students co-developed an open educational resource (OER) with their lecturers using Smith's critical reflection as a method to guide reflection on their learning. This study is significant since student learning on the co-development of an open educational resource could not be found in the literature. Within an interpretative paradigm, we used questionnaires with mainly open-ended questions to determine a particular group of students' learning. Findings indicate learning about themselves, their interactions, and their contexts. The study puts forward specific implications to improve future practices based on the findings. The specific contribution is that students who engage in critical self-reflection change their perspectives, allowing them to self-examine and reflect on future actions. This learning experience assists students, lecturers and institutions of higher education in their approach toward critical reflection and the co-development of OER.