数学教育における教材開発の研究Ⅳ — 繰り下がりのある減法の指導における論点の再考察 —数学教育における教材開発の研究Ⅳ — 繰り下がりのある減法の指導における論点の再考察 —AA11458538 Development of teaching materials in the study of Mathematics IV − Reconsideration of Subtraction by Borrowing −
Reconsideration of Subtraction by Borrowingthere are "Genka-ho (Minuend decomposition)" and "Gengenpo(Subtrahend decomposition)". Teaching that emphasizes Genka-ho does not match now. The reason iscalculation by a machine. Thus, humans must be considered how to calculate diverse.It must be able to select theappropriate calculation by the formula. Thinking the way of "Gengen-po" is significant.There was a new difficulties to "Gengen-po".It is the second operation of the subtrahend.It is necessary toconsider the rest of the subtrahend in the second operation.It is necessary to plan that careful consideration thechildren of the actual conditions.