The examination of middle school matematics teachers' geometry-based courses in the context of geometric reasoning processes

In this thesis, it is aimed to reveal the current behavior of teachers in the context of cognitive and perceptual processes in geometry teaching and to evaluate how these concepts are emphasized. In order to analyze the cognitive and perceptual processes related to geometry teaching and to contribute to the teaching of geometry, the video recording of the five mathematics teachers was analyzed according to the theoretical framework of geometric reasoning defined by French psychologist Raymond Duvall (1995). In this study, case study pattern, which is one of the qualitative research methods, is used in accordance with the nature of the study. The data obtained from video recordings were analyzed by descriptive analysis method. For the descriptive analysis, the analysis framework defined in Duvall (1995, 1996 and 1998) and defined by Güven and Karpuz (2016) was used. According to the findings obtained from the research, it was seen that the most emphasis was on visualization and reasoning code of the mathematics teachers' courses with geometry. Duval, visualization code and visual perception code; The code of creation and the sequential code of identification support each other. In addition, there is no hierarchical structure between the codes in the cognitive and perceptual process categories, but the codes can be independent of each other and interact with each other simultaneously (1998). In this respect, it is seen that the geometric reasoning processes of the teachers whose videos are analyzed coincide with the theoretical framework of Duval. Undoubtedly, all these processes Duval put forward, the students can make geometric inferences, using theorems and geometrical properties, to develop their spatial abilities, geometric skills, imagination and geometric insights, to be able to discover the transformations between geometric models and to connect the concepts play.