Science education is often presented at school by setting up practical-based activities to stimulate children's reasoning and learning, as research clearly recognizes the role of argumentation as an inquiry-based approach common to various learning experiences for the children's achievement of high-quality results (Erduran & Jiménez-Aleixandre, 2008). However, how teachers work on semiotic aspects of argumentation is still less explored (Convertini, Arcidiacono & Miserez-Caperos, 2024). For this reason, we decided to focus on teachers' interventions in science education and on the role of different semiotic resources that are mobilized during argumentative interactions with pupils. A collaboration between teachers and researchers has been set up, with the aim of designing a device enabling teachers to work with children so that the latter can learn to think argumentatively during problem-solving situations. The following questions were addressed: How practice-based science experiences settled up by teachers shape children's argumentation in classroom? How teachers' interventions mobilizing different semiotic resources support argumentation in science? Which are the main features of children's argumentation during these practices in science education?
In our investigation, we have involved 39 children (6-7 years old, grades 3-4) and 3 teachers, coming from two different classrooms recruited on a voluntary basis in the French speaking-part of Switzerland. Different practice-based tasks inviting children to discuss around science phenomena were video-recorded and then transcribed.
Through the lenses of the pragma-dialectical approach, we selected the argumentative discussions emerging during the observed experiences and we analyzed different semiotic resources (speech, gaze direction, deictic gestures, and position of physical objects) mobilized by the participants during their argumentative exchanges.
The findings show the crucial role of teachers in sustaining children's argumentation by the integration of different semiotic resources during the activities. This reveals the importance of mobilizing various communicative tools to favor children's learning in science education at primary school.