The purpose of this study was to investigate how teachers' rational questioning strategies support students' collective argumentations in the 5E-based flipped classroom approach using GeoGebra. The participants of this study were 18 seventh-grade students. Technology-enhanced tasks, audio recordings, and dynamic constructions of the participants were used as data collection tools. The analysis of the qualitative data was based on the teacher rational questioning framework and Toulmin's model. The results indicate that in the 5E-based flipped classroom approach using GeoGebra, the teacher's rational questioning regarding the area of the circle encompasses epistemic, teleological, and communicative components (by Habermas' lens). Teacher's questions including different rationality components (epistemic, teleological, and communicative) encourage students to contribute to various elements of reasoning (e.g., generalizing and justifying) and thus support collective argumentation in mathematics classrooms. In the teachers' rational questionings through the 5E-based flipped classrooms using GeoGebra, the students created productive arguments using different representations for the area of the circle in their collective argumentations.
