This research aimed to find out the effectiveness of the implementation of a metacognitive strategy toward students’ understanding of mathematical concept ability. The population of this research was all students of grade 8th of SMP Negeri 36 Bandar Lampung in the academic year of 2019/2020, consist of 172 students that were distributed into six classes. By using a purposive sampling technique, VIII E consists of 28 students, and VIII F consists of 28 students who were chosen as the research sample. This research used the pretest-posttest control group design. The data of this research was quantitative data obtained by the test of student’s understanding of mathematical concept ability. By using the t-test and proportion test, conclusions are obtained that the implementation of the metacognitive strategy was effective towards student’s understanding of mathematical concept ability.

Keywords: effectiveness; metacognitive strategy; understanding mathematical concepts

DOI: http://dx.doi.org/10.23960/mtk/v8i2.pp138-152