Development of 11th grade students' mathematical reasoning in a STEM-based learning environment

This study aimed to develop the mathematical reasoning of eleventh grade students in a learning environment designed based on STEM. In the method of the study, the study was conducted with a teaching experiment, one of the qualitative research methods, in line with the purpose of the study. In order to determine the participants, the PISA-1 test was applied to 35 students studying at an Anatolian High School in Kilis before the application. Seven participants were determined with the descriptive analysis of the data obtained in the interview after PISA-1, with at least one participant from each level in terms of reasoning competencies. Six different teaching experiments designed based on real life with the STEM approach were carried out and interviews were conducted after the tests at the beginning, middle and end of the research process. As a result of the research, the mathematical reasoning levels of all participants were examined one by one. While some participants could advance to two levels of proficiency, some remained at the same level. It was observed that although the participants had difficulty in developing in the formulation process, they developed relatively more easily in the interpretation and evaluation process. It was also observed that they turned to question solutions in different ways in the formulation process.