O Cálculo Mental na Resolução de Problemas de Subtração

Abstract

This article refers to a part of a study made by the first author, as part of a dissertation, that had the main purpose to understand which mental calculation strategies are used by first grade pupils in addition and subtraction problem solving, in order to understand how the addition and subtraction situations, presented in the problem, influenced the strategy of mental calculation used in its resolution.

Considering the purpose of the study, a qualitative methodology was conducted and three case studies were held. The study fieldwork was conducted in a first grade class and the first author was the teacher and the researcher. The class pupils solved two problem chains and all problems were solved in pairs. Later on, at the beginning of the second grade, the three studied pupils solved a third problem chain individually.
In this article, it will be presented and discussed the mental computation strategies used by one of the studied pupils in the subtraction problems of the three problem chains, seeking to highlight the most significant aspects related to the mental calculation strategies used and how these were influenced by the subtraction situation problem.