Students' argumentation schemes in terms of solving tasks with negative numbers

International audienceIn the context of an experimental project targeted at improving the teaching and learning of negative numbers, we explored the argumentation schemes of students in terms of solving respective tasks. The test items used to record the learning progress of the students were taken from the large-scale PALMA-study. While learning gains were above average, the argumentation schemes of our experimental students show both, expected and unexpected patterns. Interestingly, we find well performing students with a preference for metaphorical reasoning instead of a mixed argumentation including formal reasoning