A mediação semiótica de instrumentos culturais na aprendizagem do conceito de radioatividade no Ensino Médio

Abstract

This work is a qualitative research of empirical character carried out with high school students in the city of Goiania. Its purpose was to investigate and describe the response of the students in classroom when using different cultural tools in learning the concept of radioactivity, thus discursive dynamics has been the subject of study. The recurring debate on this issue, after the ocurrence of a tsunami in the first half of 2011 in Japan, became a reference for the elaboration of a didactic sequence titled "From nuclear instability to social instability". In the study, two interventions were conducted in different schools of Goiânia. Although only the second intervention has been analyzed, the experience gained in the first one helped us and had a close interplay with the following intervention. The data were collected from the field journal and audiovisual recordings of the classes, that were transcribed later. The whole conception of the research was strongly supported by the theory of mediated action of James Wertsch. In addition, we turned to the study of language of Bakhtin to perfom the analysis of the selected teaching episodes. Three categories of analysis were prepared a posteriori and showed, through the use of cultural tools and conceptual elaboration, recurrent features in dialogues that took place in classroom, between students and between students and the teacher. Although students have advanced on the macroscopic elaborations and extrapolated the limits of the selected cultural tools, which evidences assimilation, there were also restrictions and limits on microscopic elaborations. We understood that, unlike the textbook, which was intentionally produced to be used in the classroom, the cultural tools employed had other purposes; thus it is necessary methodological caution in the pedagogical action, when elaborating a didactic sequence with characteristics similar to the one developed here. We emphasize, then, the important role of the teacher in negotiating meanings and assisting students to move across different cultural tools.