<![CDATA[This research was motivated by the low level of understanding among fifth-grade students at SD Inpres 3 Toili regarding the area and perimeter of flat shapes, due to limited learning media and the low utilization of technology in the learning process. The objective of this study was to develop an Android-based Matda (Flat Shape Mathematics) application that meets the criteria of feasibility, practicality, and effectiveness for the circumference and area of ??flat shapes. The research method used was development research using the ADDIE (Analysis, Design, Development, Implementation, and Evaluation) model. The subjects were eight fifth-grade students at SD Inpres 3 Toili, Banggai Regency. In the feasibility test, the Matda application was validated by a team of experts. The summary of validation results from three experts (media experts, material experts, and user experts) yielded a score of 93.7%, categorized as "very feasible." For the practicality test, the researcher used a teacher response questionnaire, which yielded a score of 96.4%, and a student response questionnaire, which yielded a score of 94.1%, categorized as "very practical." In the effectiveness test, researchers used evaluation through pre-tests and post-tests. The average pre-test score was 38.5 and the post-test score was 91.3. The difference between the pre-test and post-test scores was 52.8. The N-Gain Score of 0.85 places this improvement in the "High" category. This means there was an 85.8% increase in the "effective" category. Thus, the Matda application is proven to be effective, practical, and suitable for use in elementary school learning. ABSTRAK Penelitian ini dilatarbelakangi oleh masih rendahnya pemahaman siswa kelas V SD Inpres 3 Toili dalam materi luas dan keliling bangun datar yang disebabkan keterbatasan media pembelajaran serta rendahnya pemanfaatan teknologi dalam proses belajar. Tujuan penelitian ini adalah mengembangkan aplikasi Matda (Matematika Bangun Datar) berbasis Android yang memenuhi kriteria kelayakan, kepraktisan, dan keefektifan pada materi keliling dan luas bangun datar. Metode penelitian yang digunakan adalah penelitian pengembangan dengan menggunakan model penelitian ADDIE (Analysis, Design, Development, Implementation, dan Evaluation). Subjek penelitian ini adalah peserta didik kelas V SD Inpres 3 Toili Kabupaten Banggai yang berjumlah 8 orang. Pada uji kelayakan, aplikasi Matda diuji melalui validasi oleh tim ahli. Rekapitulasi hasil validasi dari 3 ahli yaitu ahli media, ahli meteri, dan ahli pengguna diperoleh persentase sebesar 93,7% dengan kategori “sangat layak”. Pada uji kepraktisan, peneliti menggunakan angket respon guru dengan persentase sebesar 96,4% dan angket respon siswa memperoleh persentase sebesar 94,1% dengan kategori “sangat praktis”. Pada uji keefektifan, peneliti menggunakan evaluasi melalui pre-test dan post-tes. Hasil rata-rata nilai pre-test sebesar 38,5 dan post-tes sebesar 91,3. Selisih nilai pre-test dan post-test sebesar 52,8. Hasil N-Gain Score sebesar 0,85 menempatkan peningkatan ini dalam kategori “Tinggi”. Hal ini dapat diartikan terdapat peningkatan dengan persentase sebesar 85,8% kategori “efektif”. Dengan demikian aplikasi Matda terbukti efektif, praktis, dan layak digunakan dalam pembelajaran di Sekolah Dasar. ]]>
