Achievement in estimation of deaf students. A comparison between students from Brazil and Colombia

Abstract

Numerical estimation is one of the basic numerical skills associated with subsequent mathematical performance, however it has been poorly explored within deaf population. This is the first study that has analyzed this kind of performance through numerical estimation tasks, in order to define which model of representation is better adjusted with such performance. Participants were 52 deaf students from Cali-Colombia and Porto Alegre-Brazil, from 1st to 4th grade of elementary school, who performed a number estimation task on the number line. The results shown differences between Brazilian and Colombian students. The latter displayed a more stable performance and were more accurate in their estimates than the Brazilian ones, mainly in the 1st grade. In addition, Colombian students shown a stronger tendency to use linear type representations for the task.  For Brazilian students, greater increase of the accuracies was identified in higher grades and a greater variety of representations was used according to the numerical context. It is proposed that the factors of the sign language of each country as well as the pedagogical aspects may be influencing these differences, however, more studies are necessaries to improve these conclusions.