Journal article
Jurnal Khazanah Sekolah Dasar
• August 2017

The background of the present research is the previous studies' results and PISA 2015 study's results that showed the lack of mathematical communication skill in Indonesian students. This research aims at identifying the improvement of students' mathematical skill and identifying the mathematical skill of the students that get the exposure of discovery learning method in the learning process compared to those with conventional learning process. The learning process with discovery learning method consists of stimulation, problem stating, data collection, data processing, verification and conclusion making. This research was conducted using the nonequivalent pretest-posttest control group quasi-experimental design to two third-grades classes in Jatinangor District. The instruments used in this research was mathematical communication skill test items. The average difference test result of one sample to the normalized gain of students that get the exposure of discovery learning method in the learning process resulted in the significance score of 0.00. This means that there is an improvement in the students' mathematical communication skill in learning processes. The average difference test result of two samples to the posttest score data resulted in one directional significance score of 0.0015. This means that the students that got the exposure of discovery learning method in the learning process have better mathematical communication skill compared to the students with conventional learning process. It can be seen from the posttest score average of the students that get the exposure of discovery learning method in the learning process, which was 67.55, and the posttest score average of the students with conventional learning process, which was 55.48. It can be concluded that the implementation of discovery learning method is more effective compared to a conventional learning process in improving students' mathematical communication skill. The researcher recommends the implementation of discovery learning method as one of learning methods to use to improve students' mathematical communication skill.