Proving skills in geometry of secondary grammar school leavers specialized in mathematics

Abstract

We examined the evolution of the van Hiele level of some study groups specialized in mathematics from 2015 to 2018, then selected two of these groups and measured the students’ proof skills by Zalman Usiskin’s proof test. We examined whether students were able to read from the text of the statement the given fact and the fact to be proved, whether they were able to draw a figure and, using the labels, whether they were able to perform a simple proof requiring 2-3 steps.