“…Looking at problems described above, the teacher should conduct a continuously innovative teaching process because it is one of the topics having the largest part of the curriculum. Several previous studies suggest that to use open problem-based and structured problem-based learning (Herman, 2007), problem solving of real world (Bayazit, 2013;Freudenthal, 1991), a constructivist approach, integrated learning and student-centered technology (Fatimah, Norazzila, & Rohani, 2013) collaborative learning (Adolphus, Alamina, Aderonmu, Education, & State, 2013) clinical interviews, error analysis, observation or video recording in resolving problem (Joseph, 2011), diagnostic tests , for improvement toward mathematical thinking ability (Herman, 2007) so that not only on the knowledge and application level, but also on the reasoning level. Therefore, Realistic Mathematic Education (RME) is one of the potential methods including open problem-based, problem solving of real world, collaborative learning and error analysis.…”