Penelitian ini merupakan penelitian dan pengembangan yang bertujuan untuk mengembangkan big book untuk pemahaman membaca siswa, mengetahui pemahaman membaca siswa dan kelayakan media big book. Penelitian ini menggunakan penelitian dan pengembangan atau research and development (R&D) yang dikembangkan oleh Lee, W. W dan Owens, D. L yaitu ADDIE. Menurut Muhammad Rusdi (2018: 37) ADDIE bukanlah sebuah model, tetapi tahapan umum yang mana semua tahapan dalam mendesain dan mengembangkan yang dilakukan oleh para peneliti dan praktisi dapat difragmentasi menjadi fase-fase anaylsis, design, development, implementation, and evaluation. Instrumen pengumpulan data yang digunakan yaitu wawancara, observasi, lembar validasi, lembar angket pemahaman siswa terhadap media big book, dan dokumentasi. Produk media big book menghasilkan big book dengan ukuran A3, yang dicetak menggunakan kertas art paper, dan terdiri dari 10 halaman. Validasi dilakukan oleh para ahli yaitu ahli media, ahli bahasa, dan ahli praktisi. Hasil validasi ahli media sebesar 68,83%. Hasil validasi ahli bahasa sebesar 86%. Hasil validasi ahli praktisi sebesar 90,4% dan hasil dari angket pemahaman siswa sebesar 95,3%. Hasil validasi dari ahli media, ahli bahasa, dan ahli praktisi menunjukkan bahwa media big book untuk pemahaman membaca siswa kelas II-A di SD Negeri 014 Tarakan dikatakan Layak untuk diuji coba. Hasil angket respon siswa mengenai media big book untuk pemahaman membaca siswa dikatakan sangat layak digunakan untuk pemahman membaca siswa.

Kata Kunci: Penelitian dan Pengembangan, Big book, Pemahaman Membaca

This research and development study aimed to develop big books for reading comprehension of second grade students at the SDN 014 Tarakan. In addition, it aimed to determind the feasibility of the big book, and to determind students' understanding of the contens of the book. It used research and development (R&D) method of ADDIE that was developed by Lee, W.W and Owens, D.L. According to Rusdi (2018: 37) ADDIE is not a model, but a general stage where all stages in designing and developing can be fragmanted into phases of Analysis, Design, Development, Implementation, and EValuation. The data collection instruments used were interviews observations, validation sheets, questionnaires for students' understanding of the big book media, and documentation. The big book was produced in A3 papersize, which was printed using art paper, and consisted of 10 pages. Validation was carried out by experts, namely media experts, linguists, and expert practitioners. the results of media expert validation was 68.83%. The results of validation by linguists was 86%. The results of the expert practitioner validation was 90.4%, and the result of the student understanding quistionnaire were 95.3%. The results of student respomding to the questioner was 100%. The validation results from media experts, linguists, and expert practitioners showed that the big book was feasible to be tested. The results of the student response questionnaire showed that the big book was very suitable for use for the students' reading comprehension. Keywords: Research and Development, Big Book, ADDIE Research Stage, Reading Comprehension