Secondary school students’ conception about the concepts of average and data dispersion

Abstract

This work investigates how a group of secondary school students deals with sets of experimental data in the Physics laboratory. In particular, it focuses on how the students represent the best value of a physical quantity through a set of repeated measurements, and the meanings they take into account for the computation of the average value. The paper also examines the development of students’ ability to judge the quality of data, considering the data dispersion. In total, 250 students from the 1st year of high school participated in at least one of the phases of the research, which consisted in the application of two tests, one at the beginning and one at the end of the school year. For this group of students, a certain level of sophistication was identified on their representations of experimental data and their understanding of the related constructs. Based on these results, we discuss the educational implications and propose new possibilities for research in the area.