Uma investigação com alunos surdos do ensino fundamental : o cálculo mental em questão

Abstract

This research aimed to identify the didactic and pedagogical possibilities of a systematic work with mental calculation, in a dialogic way using Sign Language (Libras) with fluent deaf students, considered here as individuals who understand and interact with the world through visual experiences, being the Sign language the most important of these experiences. The investigative question was 'What are the strategies used by deaf students in teaching situations of mental calculation? The research was theoretically supported on Vergnaud's Theory of Conceptual Fields; on researches addressing the specificity regarding Sign Language and those addressing Attention Deficit Hyperactivity Disorder (ADHD); on researches on mental calculation and the Decimal Numbering System (DNS), and the elementary operations of the Additive Conceptual Field. The methodology chosen was Didactic Engineering, with the implementation of a didactic sequence composed of two blocks: the DNS and the additive. The research subjects were three deaf students who attended the end of the 6th year at the beginning of the research. The main results were: subjects were still at the building process of DNS, with the notion of the numbers "ad infinitum" related not only to the extension of the numerical sequence, but mainly to the consolidation of the rules of this system; that differentiating between spoken numbering and numbering writing was a challenge to be overcome at the DNS block; the deaf, when counting, require a combination of several elements, such as the hand gesture to indicate, the look and the hand again to signal the numbers and that, in some cases, can make counting difficult. The main strategies they used focused on the following: we observed counting from the first number uttered (not performing an overcounting); perform overcounting with and without the aid of fingers; perform countdown with and without the aid of fingers; use embedded calculations in their numeric repertoire; mentally reproduce the algorithm, using automated rules; apply numbers and operations properties and perform calculations based on the perception of some regularities of the announced numbers. The dynamics employed favored attention, self-control, and self-confidence of deaf individuals diagnosed with ADHD.