The estimation of length, surface area, and volume by blind and sighted children

Abstract

In this article, we explore the ability of blind and sighted children to estimate and measure. We are mainly concerned with the estimation of length, surface area, and volume. The investigation was conducted through questionnaires given to blind and sighted children. The questions were multiple choices and, for each question, there were three or four possible answers. The sighted children were asked to mark the correct answer, while the children with visual impairment were asked to tell us which answer they considered to be correct. Generally, from our results, we can conclude that students with visual impairment conceive the estimation of length, surface area, and volume better in concrete concepts and concepts that are familiar to them, when compared to sighted students. This is because children with visual impairment use measurement in their everyday life in order to explore their surroundings and to increase the control they have over their lives and their environment.