Development of middle school students' geometric reasoning in the context of quadrilaterals

The aim of this study is to investigate the development of geometrical reasoning of seventh grade students associated with quadrilaterals (trapezoid, parallelogram, rhombus, rectangular, square). In the research, qualitative research methods were adopted in collecting, analyzing and interpreting the data and teaching experiment was used in this context. The application of the study was carried out with 26 students in a public secondary school located in the middle-low level region of socio-economic status in Eskişehir city center in 2017-2018 academic year. Nine students selected from these students are the focus participants of the research. In the research process, pre-clinical and post-clinical interviews and eight teaching episodes which lasted for 25 lessons were designed. In the first teaching episode, emphasis was given to the features of definitions and making definitions. In the following teaching episodes, it was observed that the students were able to classify the types of quadrilaterals when they conceptualized the definition features. It has been shown that both the cognitive and perceptual processes of the students can be revealed clearly with the billiard game activities applied in the last part of the teaching process. At the end of the research, it was seen that students' apprehensions of geometric problems which were prepared according to apprehension types suggested by Duval, approached the discursive apprehension type. In addition, it has been determined that classroom activities prepared appropriately for the apprehension types revealed a significant impact on post clinical interviews.