#### 2000OA小学校児童による有理数の乗法における乗数効果の分析

vol.22, pp.206-215, 2007-03-05

The purpose of this study is to identify the multiplier effect in elementary school students from 4th to 6th grades who had already learned multiplication, and to investigate how to overcome it. For this purpose, we set the two viewpoints of i) the consciousness about the size relation of multiplier, multiplier, and product, and ii) the relation with results of ×0 and ×1, and a questionnaire investigation for students is carried out in order to inquire the feature and tendency of their understanding. According to the questionnaire for 638 students in four elementary schools, it checked that multiplier effect was especially seen in the 4th and 5th grade students. Moreover, in order to explore the cause, the consciousness of students who show the multiplier effect was followed up by using the selection problem and case method. These results showed that (1) the students who show multiplier effect especially tends to take notice of the size relation between multiplier and multiplier. (2) leanings of ×0 and ×1 could not prevent the belief "becoming large whenever it multiply", and these suggested that the consistent consideration of supports in teaching of integer, rational numbers, proportion and ratio was required.

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@kamo_hiroyasu https://t.co/9th9Te1giP からダウンロードできる文献の中の「面積などの〈乗数と被乗数を区別しない文脈〉が密接に関連し、「ひとつ分×いくつ」（〈乗数と被乗数が区別される文脈〉）とは異なるものと考えられます
@YM0MT @A5mp2KKw1VQ4tgq @lay_yamato @hyakutanaoki 嘘だと思うならちゃんと調べました？ https://t.co/qFkAmasisL 参考にした文献の1部リンク貼っておきますけど見れますかね？
@reajap_1997 @hyakutanaoki あと、https://t.co/N9AMryRLNz から見られるように、後々の指導についても効果を考える必要があると思われます。 数学的に正しいことがいつも教育的に正しいとは限りませんので…