Uma sequência didática para abordar o Sistema Internacional de Unidades

Abstract

This work describes elaboration of a didactic sequence about the International System of Units (SI). In this century, pollution plays a central role and was problematized through didactical dialogue was chosen as a teaching strategy, whose main goal is to improve significant levels of interaction between students and the teacher. Link this theme to the seven basic SI units, contextualizing and relating them to each other was our challenge, motivated us to base it on Guy Brousseau's Theory of Didactic Situations. The five phases recommended by this theory are devolution, action, formulation, and institutionalization, alternating didactic and adidactic situations. Students acted as agents to their thoughts structuring, actively participating in the knowledge construction process. The sequence was applied to a third-year high school class at a public school in Franca-SP city. It catalogs situations in which, starting from idealized problems supported by real data, students have chosen and tested resolution strategies related to measurement of physical interest quantities and data treatment. In the institutionalization phase, basic units of SI standardization and its current definitions in universal constants terms were systematized and the problematic question was taken up, specifically oceans pollution caused by inappropriate plastics disposal and light pollution. These activities were organized in the educational product entitled Quantificação e o Novo Sistema Internacional de Unidades: pensando em algumas faces da poluição, which join also a brief history of SI, and the names and symbols official rules. The results obtained point to a good students approval to tasks execution and discussions, resulting from questioning strategies implemented, with wide logical reasoning use. The need for good contextualized practices, appeal to students' interest and participation, contributing to a more effective teaching and learning process and must be widely disseminated.