2003 年 27 巻 2 号 p. 111-119
A new curriculum based on stundent's informal knowledge in ratio was established in the present study. The goal of this study was to examine the effect of the new curriculum on students' understanding of ratio. The ratio concept as a quantity rather than symbol operations was stressed in the new curriculum. In addition, the second term of proportion (b × p=a ; b : base quantity, p : proportion, a: quantity to be compared) was introduced first in the sequence of teaching three terms on ratio. Thirty-five students participated in eight lessons based on the new curriculum and 71 received normal lessons following the textbook. The students of the experimental group showed significantly superior performance over the textbook group (control group) in solving ratio problems. Although computational strategy was used in the textbook group in problem solving, an estimation strategy was mainly adopted in the experimental group. These results are discussed from the viewpoint of curriculum based on informal knowledge in children.