The objectives of this study are (1) to describe the quality of good Learning devices on validity, effectiveness and practicality, (2) to describe improvement in learning outcomes of fourth grade Elementary School students by using realistic mathematical approaches in fraction material. This research is a development research by using 4-D model that is defining, designing, developing and disseminating. The validation results proved that the learning devices is valid and ready to use. Furthermore, the learning devices was tested by using One Group Pretest-Posttest Design in fourth grade class of Klampis Ngasem V Elementary School Surabaya. The results of this development showed that (1) learning devices have good quality because they achieved the following requirements; the validator's assessment of the learning devices is in a score of 4 in the valid category, the ability of the teacher to manage learning and student activities in a good category, that is more than 75% of students get A score above the minimum competence criteria (KKM) which shows that student learning outcomes are complete, and the student's positive response to the learning devices indicated by more than 75% of students gave their opinion that they were happy, get new method, clear explanation and interest in learning this material, (2) student learning outcomes of using a realistic mathematical approach has increased with gain score of 0.7.

Keywords : Realistic Mathematic Approach, Fraction Material.