The aim of this research is to investigate eighth graders’ mistakes and misconceptions of the "Slope" concept that take place in the mathematics curriculum and to make recommendations for solution. According to this purpose, the sample of the research consisted of 165 eighth graders from 4 different public schools located in Palandöken district of Erzurum province. The students of the sample were those, who were ready at the school on the day at which the research was carried out. To determine the mistakes and misconceptions of the students on the slope, a “Slope Test” consisting of 7 multiple choice questions and 8 open-ended questions, was created in accordance with the gains. Expert opinions were applied during developing the Slope test, and validity and reliance studies were carried out through a pilot study. In the research, the "Slope Test" was applied to the students and this test was used as the data collection tool. The descriptive scanning method was employed in the research and as the interview was held with some of the students if necessary, the mixed method was the method of the study. The obtained data were analyzed with the descriptive analysis and content analysis techniques. The mistakes and misconceptions of the students were examined according to the results of the study and some recommendations were made considering the results.

Keywords: Slope, misconception, eighth grade students, mathematics education.


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