The Necessity of Rethinking in the Content of 7th and 8th Grades Mathematics Textbooks from the Aspect of Reasoning and Proof

The verification of a mathematical statement is normally difficult for students; and they often face difficulty realizing its relevance and necessity. The hidden complexities in the valuable nature of reasoning and proof signal to the significance of the way of presenting them in textbooks. The aim of this study is to determine the role of reasoning, especially deductive reasoning in 7th and 8th grades mathematics textbooks which was fulfilled though a content analysis method. The results show that the highest amount of reasoning, including different kinds of deduction, is allocated to the geometric content, although unexpected findings are obtained as well. Generally speaking, deductive reasoning has not been distributed uniformly in the chapters of mathematics textbooks under study. The deficiency of deduction could be observed in many chapters related to arithmetic, probability and statistics. In addition, the experimental argumentation has been increased by two times surprisingly in the 8th grade textbook compared to that of 7th grade. At the end of the paper, some considerations are discussed that should be taken into account when addressing the shift of attention from inductive to deductive reasoning in these grades.