This study aims to find out how to apply the approach of Realistic Mathematics Education (RME) that improves student activities and learning outcomes on the topics of flat side solids. This type of research is Classroom Action Research (CAR). The subject of this research is 30 students of class VIIIA SMPN 1 Pondok Kelapa even semester of 2016/2017 academic year. The instruments used are activity observation sheets and test result of student learning. The results showed that there was an improvement in the student's learning activities by forming heterogeneous discussion groups, using visual aids in constructing mathematical ideas, guiding them to take on the task of group activities, and providing motivation and appreciation in the form of praise. Student learning outcomes can also be improved by reminding the material of previous meetings, linking the benefits of learning materials through contextual issues, giving practice questions, guiding in finding concepts through PMR-based LKPD and reminding them to read the next meeting material.