Research in teacher education is still a field dealing with open questions. One of these open fields is the incorporation of new pedagogical principles such as inquiry-based processes. In this transition encouraged by most national curricula, knowledge involved in study processes changes heavily: it moves from well-established and static knowledge to more dynamic and provisional structures. This transition causes the description, management and analysis of knowledge to be a challenge for teachers. Researchers within the Anthropological Theory of the Didactic have used question-answer maps to describe knowledge involved in the implementation of inquiry teaching formats. We propose to use these question-answer maps as a research tool to be incorporated in teacher education to empower teachers to deal with this new nature of knowledge to be taught. We present in this paper an exploratory case study of an online course for secondary teachers using question-answer maps as a tool to describe knowledge.