算数科における用語「もと」の使用に関する調査研究 算数科教科書にみる「もと」の使われ方の分析を通して

抄録

The purpose of this paper is to analyze how the term “MOTO” is used in arithmetic textbooks, to point out the characteristics of its usage, and to obtain suggestions for learning guidance toward an appropriate understanding of “MOTO”. In order to achieve the purpose of this study, we analyzed the usage of the term “MOTO” in six arithmetic textbooks. As a result, we identified that the term “MOTO” in arithmetic class can be classified into three types. The classification of the term “MOTO” in terms of grade, domain, and fraction unit revealed six characteristics of the use of the term “MOTO”. Based on these findings, we proposed a teaching material for second-grade fractions class, which emphasizes “original size”. In addition, we analyzed and discussed aspects of the children’s behavior in the study by using them as case examples. The results suggest a relationship between “original” in the sense of “original” in the second-grade fractions unit and “original” as a standard (base) that increases from the third grade onward in the study of fractions.