<![CDATA[The aim of this research is to create a digital teaching resource in the form of a flipbook that utilizes local knowledge to help students improve their critical thinking skills in the context of sequences and arithmetic series. The lack of teaching resources that integrate local culture and the low critical thinking abilities of students are the main driving forces behind this research. This study uses the 4D development model (Define, Design, Develop, Disseminate) by Thiagarajan. The research subjects are 10th-grade students of SMA Islam Diponegoro. Data collection techniques include expert validation, teacher and student response questionnaires, as well as critical thinking ability tests based on indicators of interpretation, analysis, evaluation, and inference. The research results show that the developed teaching materials meet the very valid criteria with a percentage of 94%, meet the very practical category with a percentage of 84% from student responses and 85% from teacher responses, and are highly effective with a classical completeness percentage of 70%. Therefore, the digital flipbook teaching material with local wisdom is highly recommended for use in mathematics learning to support students' critical thinking abilities. Abstrak Tujuan penelitian ini adalah menciptakan sumber daya ajar digital bergaya flipbook yang memanfaatkan pengetahuan lokal untuk membantu siswa meningkatkan kemampuan berpikir kritis mereka dalam hal deret dan deret aritmatika. Minimnya sumber daya ajar yang mengintegrasikan budaya lokal dan rendahnya kemampuan berpikir kritis siswa menjadi pendorong utama penelitian ini. Penelitian ini menggunakan model pengembangan 4D (Define, Design, Develop, Disseminate) oleh Thiagarajan. Subjek penelitian adalah siswa kelas X SMA Islam Diponegoro. Teknik pengumpulan data meliputi validasi ahli, angket respon guru dan siswa, serta tes kemampuan berpikir kritis berdasarkan indikator interpretasi, analisis, evaluasi, dan inferensi. Hasil penelitian menunjukkan bahwa bahan ajar yang dikembangkan memenuhi kriteria sangat valid dengan persentase sebesar 94%, memenuhi kategori sangat praktis dengan persentase sebesar 84% dari respon siswa dan 85% dari respon guru, dan sangat efektif dengan persentase ketuntasan klasikal 70%. Oleh karena itu, bahan ajar digital flipbook berkearifan local baik digunakan dalam pembelajaran matematika untuk mendukung kemampuan berpikir kritis siswa. Kata kunci : Bahan ajar digital, flipbook, kearifan lokal, berpikir kritis, barisan dan deret aritmatika ]]>
