<![CDATA[Penelitian ini bertujuan mengembangkan dan menguji buku saku berbasis teka-teki matematika untuk meningkatkan kemampuan penalaran matematis siswa kelas VII. Metode yang digunakan adalah Research and Development dengan model 4-D (Define, Design, Develop, Disseminate) dan melibatkan 32 siswa kelas VII-1 SMP Swasta Salsa pada semester ganjil tahun ajaran 2025/2026. Hasil penelitian menunjukkan bahwa buku saku yang dikembangkan: (1) valid dengan hasil validasi ahli materi 0,75 (layak) dan ahli media 95,5% (sangat layak), (2) praktis dengan respon siswa 0,71 (praktis) dan respon guru 0,925 (sangat praktis), serta (3) efektif meningkatkan kemampuan penalaran matematis, ditunjukkan oleh nilai N-Gain 0,322 (kategori sedang) dan hasil uji t-test yang signifikan. ABSTRACT This study aims to develop and test a puzzle-based math workbook to improve the mathematical reasoning skills of seventh-grade students. The method used is Research and Development with the 4-D model (Define, Design, Develop, Disseminate) and involves 32 seventh-grade students from Salsa Private Junior High School in the odd semester of the 2025/2026 academic year. The results of the study indicate that the developed pocket book: (1) is valid with a material expert validation score of 0.75 (acceptable) and a media expert validation score of 95.5% (very acceptable), (2) practical with a student response of 0.71 (practical) and a teacher response of 0.925 (very practical), and (3) effective in improving mathematical reasoning skills, as indicated by an N-Gain value of 0.322 (moderate category) and significant t-test results.]]>
