Fostering rational numbers understanding through percentage

International audienceThis paper discusses an approach that fosters students' conceptual understandings of rational numbers with an initial focus on percentage, in elementary school years. This approach enables students to work with multiple representations associated with percentage which are taken as models of contextualized situation and reconstructed as models for reasoning through an emergent modeling process. A classroom teaching experiment was developed following the methodological procedures of a Design Research. Data were collected through participant observation, supported in a logbook, audio-and video-recorded lessons and students' productions in the classroom. The analysis of data reported in this paper seems to highlight that through this approach, percentage-if privileged in the introductory steps of its learning-strengthens the interpretation of multiplicative relations and fosters understanding of rational numbers through an emergent modeling process