김정원 Kim Jeongwon

DOI: JANT Vol.25(No.3) 213-232, 2022

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With the importance of number line in learning fractions, this study investigated how 4th grade students understand fractions and its operations in number line. The questionnaire consisted 22 items which were related to representing fractions, comparing the size of fractions, and operating addition and subtraction of fractions. Both structured number line and sub-structured number line were presented in the items. As results of the study, the overall success rates were not high and even some items showed higher incorrect answer rates than the success rates. Also, the students showed a difficulty in solving non-structured number line tasks. It was also noticeable that students showed several types of incorrect answers, which means that students had incomplete understanding of both fractions and number line. This paper is expected to shed light on elementary students’ understanding of fractions and number line and to provide implications of how to deal with number line in teaching and learning fractions in the elementary school.

강윤지 Kang Yunji

DOI: JANT Vol.25(No.3) 233-249, 2022

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Measurement plays an important role in both school mathematics and real life. Among the measurement areas, length is the first to learn and is the basis for measurement. Time is measured in its own way and is characterized by being the most abstract. This study attempted to analyze elementary mathematics textbooks and representations in real life to examine how the length and time of learning in school mathematics differ from those represented in real life. Based on this, we tried to derive implications for the direction of measurement education and elementary math textbooks. As a result of the analysis, the concept of length was used the same in real life and school mathematics. However, terms such as distance, depth, and height were not defined, and the representation of the approximate value was presented in a fragmentary form. In addition, there were parts where students were likely to feel confused in school mathematics and real life, such as the same units such as 'minutes and seconds' were used in time. Therefore, considering these differences, it is necessary to consider the direction of composition of math textbooks and teaching and learning so that students can connect school mathematics and real life and understand widely about measurement concepts.

박만구 Park Mangoo , 박혜민 Park Haemin , 최은미 Choi Eunmi , 표정희 Pyo Junghee

DOI: JANT Vol.25(No.3) 251-278, 2022

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The purpose of this study is to obtain implications for mathematical education by analyzing how the multiplication and division of decimal numbers are presented in the elementary mathematics textbooks in Korea, Japan, Singapore, and Finland. Compared to the fact that students often have misconceptions about multiplication and division of decimal numbers, there have been not many comparative studies in recent elementary mathematics textbooks. For this study, we selected elementary mathematics textbooks those are widely used in Japan, Singapore, and Finland along with Korean elementary mathematics textbooks. We chose the textbooks because the students in the selected countries have scored high in international achievement studies such as TIMSS and PISA. The analysis was examined in terms of elementary mathematics curriculum related to multiplication and division of decimal numbers, introduction and content, real-life situations, use of visual models, and formalization methods of algorithms. As a result of the study, the mathematics curricula related to multiplication and division of decimal numbers includes estimation in Korea and Finland, while Japan and Singapore emphasize real-life connections more, and Finland completes the operations in secondary schools. The introduction and content are intensively provided in a short period of time or distributed in various grades and semesters. The real-life situations are presented in a simple sentence format in all countries, and the use of visual models or formalization of algorithms is linked to the operations of natural numbers in unit conversions. Suggestions were made for textbook development and teacher training programs.