The Improvement of Mathematic Learning Achievement through Process Skill Using Measurement Media in Muhammadiyah Sapen Elementary School

—This research was carried out because there are various problems in learning Mathematics in the class. As a solution of the problems, researchers conducted a classroom action research. The purpose of this research is to (1) develop the learning of elementary mathematics and (2) to describe the improvement of mathematics learning achievement in determining the volume, and the surface area of cube and prism building with the approach of media-aided process skill in grade V student of Muhammadiyah Sapen Yogyakarta. This research is a classroom action research. Data collection was done through observation, interview, field notes, and documentation. Data analysis technique used is descriptive qualitative and quantitative analysis. The results of the study are as follows. (1) The approach of media-assisted process assisted measure can improve mathematics learning achievement in determining cube and prism build volume in grade V SD Muhammadiyah Sapen Yogyakarta. (2) The media-assisted process-assisted approach can improve the mathematics learning achievement in determining the surface area of cube and prism building on the students of grade V SD Muhammadiyah Sapen Yogyakarta. Both of these are proven by the improvement of average and mastery of students' mathematics learning. The average of student learning increased at pre-cycle of 77, 42 increased to 78, 21 in cycle 1, and 82,60 in cycle 2. The improvement of students' conformity with the value of KKM or mastery of students in the learning on the pre cycle is that 16 students or 48.49%, complete the KKM, which later increased in cycle 1 with 21 students or 64.64%, completed the KKM and on cycle 2 there were 32 students or 96.97% completed the KKM.