<![CDATA[Pembelajaran Biologi pada Kurikulum Merdeka menekankan pendekatan deep learning untuk membentuk dimensi profil lulusan, khususnya penalaran kritis, yang selaras dengan tuntutan keterampilan abad ke-21 meliputi critical thinking, communication, collaboration, dan creativity. Namun, bahan ajar di sekolah masih terbatas dan belum optimal mendukung pembelajaran berbasis masalah serta pemanfaatan teknologi pembelajaran interaktif, khususnya pada materi Sistem Pencernaan Manusia. Penelitian ini memiliki tujuan merancang serta menilai kelayakan buku saku interaktif berbasis Problem Based Learning yang dilengkapi dengan Augmented Reality guna meningkatkan kemampuan berpikir kritis siswa kelas XI SMA. Penelitian menggunakan model pengembangan 4D dengan uji coba skala terbatas dilakukan pada 25 siswa kelas XI di SMA Negeri 7 Surabaya. Instrumen meliputi validasi ahli, angket respon siswa, observasi keterlaksanaan pembelajaran, uji keterbacaan grafik Fry, serta soal pretest dan posttest. Hasil menunjukkan tingkat validitas sangat valid dengan nilai 98.38%, kepraktisan sangat praktis berdasarkan respon siswa mendapatkan nilai 98.4% dan keterlaksanaan pembelajaran mendapatkan nilai 97.47%, serta keterbacaan yang sesuai dengan tingkat kelas XI. Keefektifan ditunjukkan oleh peningkatan nilai rata-rata dari 54 menjadi 93.2 dengan nilai N-gain sebesar 0,8 yang termasuk dalam kategori tinggi serta tingkat ketuntasan belajar mencapai 100%, dan peningkatan ketercapaian indikator berpikir kritis dari 52% cukup tuntas menjadi 94.33% sangat tuntas. Dengan demikian, buku saku interaktif dinyatakan layak, praktis, dan efektif sebagai media pembelajaran Biologi untuk meningkatkan kemampuan berpikir kritis siswa. Kata Kunci: buku saku, PBL, pembelajaran abad-21, berpikir kritis. Biology learning in the Independent Curriculum emphasizes a deep learning approach to shape graduate profile dimensions, particularly critical reasoning, which aligns with the demands of 21st-century skills including critical thinking, communication, collaboration, and creativity. However, teaching materials in schools are still limited and do not optimally support problem-based learning and the use of interactive learning technology, especially in the Human Digestive System material. This study aims to design and assess the feasibility of an interactive pocketbook based on Problem Based Learning equipped with Augmented Reality to improve the critical thinking skills of 11th-grade high school students. The study used a 4D development model with a limited-scale trial conducted on 25 11th-grade students at SMA Negeri 7 Surabaya. Instruments included expert validation, student response questionnaires, learning implementation observations, Fry graph readability tests, and pretest and posttest questions. The results showed a very valid level of validity with a value of 98.38%, very practicality based on student responses obtained a value of 98.4% and learning implementation obtained a value of 97.47%, as well as readability appropriate for the 11th-grade level. Effectiveness is demonstrated by an increase in the average score from 54 to 93.2, with an N-gain of 0.8, which is considered high. The learning completion rate reached 100%. The critical thinking indicator achievement increased from 52% (quite complete) to 94.33% (very complete). Therefore, the interactive pocketbook is deemed feasible, practical, and effective as a Biology learning medium to enhance students' critical thinking skills. Keywords: pocket books, PBL, 21st-century learning, critical thinking.]]>
