Penelitian ini dilatar belakangi oleh rendahnya pemahaman konsep luas bangun datar pada pelajaran matematika Sekolah Dasar. Tujuannya untuk mendeskripsikan aktivitas guru, siswa dan nilai pemahaman konsep luas menggunakan pentomino puzzle. Penelitian tersebut menggunakan penelitian tindakan kelas dengan subjek siswa kelas IV SDN 1 Sumengko. Teknik pengumpulan data mengggunakan lembar aktivitas guru, aktivitas siswa, tes serta dokumentasi. Presentase aktivitas guru sebesar 73,07%, 90,38% dan 97,11%. Presentase aktivitas siswa sebesar 62,5%, 93% dan 95,83%. Hasil belajar secara klasikal sebesar 23,3%, 80% dan 100%. Bisa disimpulkan bahwa penggunaan media pentomino puzzle meningkatkan pemahaman konsep luas bangun datar.

Kata Kunci: pentomino puzzle, pemahaman konsep, matematika.

The background of this research is the low understanding of the area concept of two-dimentionalfigurein elementary school math lesson. This study aims to describe the activities of teachers, students and the value of understanding area concepts using pentomino puzzles. This study uses classroom action research with the subject of fourth grade students at SDN 1 Sumengko. Data collection techniques use teacher activity sheets, student activities, tests and documentation. The percentage of teacher activity is 73.07%, 90.38% and 97.11%. The percentage of students activity is 62.5%, 93% and 95.83%. Classical learning outcomes are 23.3%, 80% and 100%. It can be concluded that the use of pentomino puzzle media enhances the understanding of the area concept of two-dimentional figure.

Keywords: pentomino puzzle, understanding concepts, mathematics.