摘要：There are 3 questions that will be answer ed in this study, namely (1) what are the context s that can be used to introduce the meaning of multiplication of two fractions and to find the result of multiplying two fraction s, (2) how to use these contexts to help students construct the understanding of the meaning of multiplication of two fractions and find the result of multiplying two fractions, and (3) what is the impact of the teaching - learning process that has been designed by researcher s on the process of student s ' knowledge construction . Learning approach which was used in developing teaching materials about fractions is realistic mathematics approach. Lesson plan was created for fifth grade elementary school students. The t ype of researc h used is development research . According to Gravemeijer and Cobb , there are three phases in development research, namely (1) preparation of the trial design, (2) the trial design, and (3) a retrospective analysis. T his paper presents the results of the first cycle of three cycles that have been planned
关键词：fractions; realistic mathematics education; design research
