*PMRI in Aceh *is one of the sub titles in a book that titled* A Decade of PMRI in Indonesia. *This book was written by Rahmah Johar in 2010.

According to Gravemeijer that was quoted by Rahmah, RME (Realistic Mathematics Education) is a theory of mathematics learning that uses reality as the starting point in the learning process and aims to support the students in reinventing mathematics in problem-centered interactive instruction. Since 1968, Netherland has been developing that learning approach. And Indonesia has been adaptating it as PMRI (Pendidikan Matematika Realistik Indonesia) since 1998. In Nanggroe Aceh Darussalam, the local PMRI-team of University Syiah Kuala began socialization of PMRI in 2006, such as conducting workshop, doing research, writing student textbook, and coaching primary school teachers. There is a significant progress, even thought there is still challenges in the future.

Beside abstraction and formalization, difficulties in learning mathematics is caused by the style of teaching that is meaningless. While teacher is only explain the mathematics concept or procedures and give an example, the students have to listen, write down, and do the exercise. They quickly forget the content and can’t apply it in the daily activity. It isn’t equal with the realictic approach. In the realistic approach, student rebuild their mathematics idea, explore concepts by their creativity and initiatives. They are regularly organized to work in groups, so they can discuss and learn to respect different opinions and solutions. According to Sembiring, it is not only reform the mathematics education, but also teaching democratic culture. Beside that, it is suitable with KTSP. According to this curriculum, students have to be engaged in learning experiences, involving mental and physical process through interaction between students and students, students and teacher, students and their environment, as well as students and learning resources.

Hans Freudental (Gravemeijer, 2010) argued that students should be engaged in mathematics as a human activity that means an activity of solving problems, looking for problems, and organizing a subject matter. To implement RME, the teacher needs to design realistic problem to be discussed in the classroom and have to be a mediator and facilitator.

The socialization of PMRI in Aceh started in 2006. Cooperation was sought with the teacher educators of other Teacher Education Colleges in Aceh, the Institute for Quality Assurance of Aceh province, and local Department of Education of province. The goals of that socialization such as to inspire teachers and get them acquainted with that approach and to be willing and confident to implement it in their class. Now, there are 36 primary schools that have connected to the local PMRI center. From each school, 5 teachers, one from each grade 1 to 5 are involved in the socialization. In the first year, workshops focused on Grade 1 and 2, in the second year, it focused on Grade 3 and 4, and in the third year, it focused on Grade 4 and 5. The topics of these workshop are simulation of teaching, discussion about students’ thinking, analizing videos, and reflections and planning follow up activities.

The simulation is leaded by a teacher educator or a key teacher, a teacher who has gained ample experience in the implementation of PMRI and can share their experiences. The consultant from Netherland could also give comment and reflect. When discussed about students’ thinking, teachers analized the students answer. There are many videos, such as measurements of length, measurements of weight, the net of cube, volume, area and perimeter, and integer number. Then, it would be followed by implementing of PMRI.

Not only in the development of RME, the concept of a hypothetical learning trajectory is used in socialization of PMRI in Aceh. The teachers have to design a learning route/learning trajectory around a well specified topic that is supported by the teacher educators of the local PMRI-center. The main focus of this reseach is the frequency of students’ interaction that is analysed by making sociograms. The categories of students’ interactions such as the student/teacher explains the question, the student asks question to student/teacher, the student responds to a question from student/teacher, the student answers the question from student/teacher, and students do irrelevant activity (for example: run away or day dreaming). After analizing data, it will be made conclution.

Writing material is very important in socialization of PMRI in Aceh. It supports analizing the curriculum, thinking about ways of changing the teaching strategies, and coaching the teacher in the school.

There are over 2000 schools in Aceh. Therefore, there are many strategic plan to implement PMRI there, such as institutionalize the local PMRI center, increase the intensity of the contacts among elements, increase the number of people who do design reseach on PMRI, continue and expand the cooperation with international teacher training institutes, and continue with designing and writing Islamic PMRI lesson materials.

Based on the experience of implementation of PMRI in Aceh, we able to learn that RME is a mathematics learning approach that is meaningfull so students are motivated to reinvent of mathematics idea by their creativity and inisiative. Teacher isn’t dominant in the class but they become the mediator and fasilitator. Interaction is very important, not only between student and teacher but also between student and student, and between student and learning resources. To implement PMRI, we should engage many elements of education to do workshop, writing material, and follow up.