Introdução à geometria plana - ângulos: análise da organização didática em livros didáticos do 8º ano do ensino fundamental

Abstract

This study aimed to analyze the approach of the concept of angles in three 8th grade of elementary school textbooks approved by the Brazilian Ministry of Education and Culture (MEC). Thus, this study purpose was to answer the following question: Do textbooks develop content relating to Angle, in Plane Geometry, proposing activities and using other teaching tools, such as softwares, encouraging students to develop their geometric thinking? - The paper was based on the studies of semiotic records representations by Raymond Duval and the anthropological theory of teaching and organization of praxeological by Yves Chevallard. The research procedure defined three analysis criterias of textbooks and the comparison between them. The study results showed that, in all the three books reviewed in this paper, the authors emphasize the records of the mother language, figural and the use of concrete material, but none of them suggest the use of other materials as a resource for teaching the content of angles. The suggestion of using geometry software in teaching any mathematical content was not identified in any of the books studied. The authors present clear tasks with available technological framework, but the conversions are not properly explored, sticking only with the exercises set by textbooks, which does not favor the construction and development of geometric thinking by students