<![CDATA[This study was motivated by the low level of students’ critical thinking skills in science learning and the suboptimal use of contextual learning media based on local culture. This study aimed to develop a local culture-based science diorama that is valid, practical, and effective in improving the critical thinking skills of fifth-grade elementary school students. This study employed a Research and Development (R&D) method using the DDD-E model, which consists of Decide, Design, Develop, and Evaluate. The effectiveness test involved 26 fifth-grade students at SD Negeri Kalia. Data were collected through expert validation, teacher and student response questionnaires, observations of learning implementation, and critical thinking skills tests. The data were analyzed using Aiken’s V, practicality analysis, N-Gain, and the Paired Samples t-Test. The results showed that the local culture-based science diorama had high validity, with an Aiken’s V coefficient of 0.99. The practicality of the media was indicated by teacher and student responses of 91.6% and 91%, respectively, while learning implementation reached 94.23%, categorized as very good. Students’ critical thinking skills increased from a mean pretest score of 41.95 to a posttest score of 86.44, with an N-Gain score of 0.77, categorized as high. Improvements occurred across all critical thinking indicators: interpretation (0.75), analysis (0.77), evaluation (0.78), inference (0.86), and explanation (0.74). The highest improvement was found in inference (0.86), while the lowest was found in explanation (0.74), although both were categorized as high. The Paired Samples t-Test yielded a significance value of 0.000 (p < 0.05), indicating a significant difference in students’ critical thinking skills before and after using the media. Therefore, the local culture-based science diorama was considered valid, practical, and demonstrated effectiveness in supporting the improvement of fifth-grade elementary school students’ critical thinking skills.. ABSTRAK Penelitian ini dilatarbelakangi oleh rendahnya keterampilan berpikir kritis siswa dalam pembelajaran IPA serta belum optimalnya penggunaan media pembelajaran yang kontekstual dan berbasis budaya lokal. Penelitian ini bertujuan mengembangkan media diorama IPA berbasis budaya lokal yang valid, praktis, dan efektif untuk meningkatkan keterampilan berpikir kritis siswa kelas V sekolah dasar. Penelitian ini menggunakan metode Research and Development (R&D) dengan model DDD-E yang meliputi Decide, Design, Develop, dan Evaluate. Subjek uji efektivitas terdiri atas 26 siswa kelas V SD Negeri Kalia. Data dikumpulkan melalui validasi ahli, angket respons guru dan siswa, observasi keterlaksanaan pembelajaran, serta tes keterampilan berpikir kritis. Data dianalisis menggunakan Aiken’s V, analisis kepraktisan, N-Gain, dan Paired Samples t-Test. Hasil penelitian menunjukkan bahwa media diorama IPA berbasis budaya lokal memiliki validitas tinggi dengan nilai Aiken’s V sebesar 0,99. Kepraktisan media ditunjukkan oleh respons guru sebesar 91,6% dan respons siswa sebesar 91%, sedangkan keterlaksanaan pembelajaran mencapai 94,23% dengan kategori sangat baik. Keterampilan berpikir kritis siswa meningkat dari rata-rata skor 41,95 pada pretest menjadi 86,44 pada posttest, dengan nilai N-Gain sebesar 0,77 yang termasuk kategori tinggi. Peningkatan terjadi pada seluruh indikator, yaitu interpretation (0,75), analysis (0,77), evaluation (0,78), inference (0,86), dan explanation (0,74). Peningkatan tertinggi terdapat pada indikator inference (0,86), sedangkan terendah pada explanation (0,74), meskipun keduanya berada dalam kategori tinggi. Hasil Paired Samples t-Test menunjukkan nilai signifikansi 0,000 (p < 0,05), yang menunjukkan adanya perbedaan yang signifikan antara keterampilan berpikir kritis siswa sebelum dan sesudah penggunaan media. Dengan demikian, media diorama IPA berbasis budaya lokal dinyatakan valid, praktis, dan menunjukkan efektivitas dalam mendukung peningkatan keterampilan berpikir kritis siswa kelas V sekolah dasar.]]>
