O pensamento estatístico nos anos finais do ensino fundamental: o desenvolvimento da transnumeração e da construção de gráficos

Abstract

In Statistics, graphs play the role of presenting data in a way that allows the reader to quickly and easily understand a phenomenon. Thus, they constitute the main means of visualization and dissemination of statistical information. In contemporary society, marked by the supremacy of the image and visual artifacts to the detriment of writing, the capacity for synthesis and communication of graphics has been increasingly valued. However, graphics with distorted information (intentionally or not), poorly constructed or inappropriate from a scientific point of view are often published in the media and literature. In this sense, it is necessary to propose and discuss teaching methodologies that promote the development of transnumeration and the ability to build graphics, especially in Basic Education. When building a graph, an important element of statistical thinking is mobilized: transnumeration. In this research, the general objective was to propose the development of transnumeration and the ability to construct graphs by students in the final years of Elementary School, in the light of the theoretical and methodological assumptions of Didactic Engineering. The literature review showed work proposals in the classroom aimed at the development of transnumeration and the ability to build graphs. Based on the methodological assumptions of Didactic Engineering, we developed a didactic sequence in order to contemplate these proposals. Thus, 17 students from the 7th Year of Elementary School participated in a project whose theme was the growing generation of electronic waste or Waste Electrical and Electronic Equipment (WEEE). The data production activities consisted, initially, in the quantitative survey of electronic products to be discarded in the students' homes and, later, in the quantitative survey of electronic products to be discarded by the entire class. Data processing activities consisted of organizing data into tables and building graphs using paper and pencil and using digital technologies. In all, 35 graphs were built. The graphs produced were presented by the students, individually, to the whole class. The results showed that the set of tasks of the didactic sequence contributed to the development of statistical thinking and, more specifically, of transnumeration. However, with regard to the construction of graphics, the students showed weaknesses notably with regard to graphic density and graphic decoration. In other words, the analytical, decision-making and technical aspects involved in the graphic construction process constituted obstacles for students to learn, mainly of a didactic nature. Thus, we found that the construction of attractive and scientifically adequate graphics is not intuitive, direct and immediate as it may seem. On the contrary, it is reflective and methodical. And so, we conclude that the skill of building graphs is not easily acquired by most students