An investigation of geometric reasoning skills of eighth grade students

In this study, it is aimed to investigate the geometric reasoning skills of eighth-grade students and to investigate the effectiveness of the focus group studies with the clinical interviews performed. Participants were conducted with 4 students of eighth grade in a state secondary school affiliated to the MEB in Karabağlar district of Izmir province. In this study, student selection was chosen by considering the two criteria determined by the researcher, which is the method of sampling criteria for research purposes. These criteria are; (i) Students have seen the concepts in geometry in the course, (ii) Students have different levels of mathematical achievements (medium and high). It has been noted that these students are students who can express themselves well. Qualitative research method was used in the investigation of data collection, analysis and interpretation. The data obtained from the study were collected by clinical interviews and focus group studies. In this data collection process, a total of 8 questions, 4 in the first focus group interview, and 5 open-ended questions in the second focus group interview were asked, with the same preliminary and final clinical interviews as the geometric reasoning. The data obtained during the research process has been analyzed on the basis of questions and each question is examined according to the subskills of reasoning and is tried to be classified as correct/defective/faulty reasoning. The data is analyzed by content analysis method. As a result of the research, students ' reasoning skills reflected in the first clinical interview are largely flawed or inaccurate, and the focus group talks positively affect each other in the final clinical interview, more accurate reasoning executions were observed. Also, thanks to the focus group interviews, peer interaction can also be beneficial and an increase in success.