Kemampuan pemecahan masalah matematis sangat penting dimiliki oleh siswa, namun pada kenyataannya kemampuan pemecahan masalah siswa masih rendah karena masih banyak siswa yang kesulitan menyelesaikan permasalahan dalam bentuk soal cerita seperti soal transformasi geometri. Hal ini karena kurangnya bahan ajar yang menunjang pembelajaran siswa, sehingga perlu bahan ajar yang membantu peningkatan kemampuan pemecahan masalah matematis siswa. Penelitian ini bertujuan untuk mengembangkan e-modul flipbook menggunakan sintaks PjBL yang dapat menunjang pembelajaran siswa dalam meningkatkan kemampuan pemecahan masalah matematis pada materi transformasi geometri. Jenis penelitian yang digunakan dalam penelitian ini yaitu penelitian dan pengembangan atau Research and Development (R&D) yang menggunakan model pengembangan ADDIE yaitu Analysis, Design, Development, Implementation, and Evaluation. Subjek yang digunakan pada penelitian yaitu 26 siswa kelas IX A di SMP Negeri 1 Hantara. Teknik pengumpulan data menggunakan angket, wawancara, dan tes. Instrumen yang digunakan dalam penelitian ini yaitu lembar validasi, lembar angket kepraktisan, soal uraian tes, dan pedoman wawancara. Sumber data diperoleh dari dosen, guru, dan siswa. Produk e-modul dilakukan uji validitas oleh validator ahli materi dan media. Hasil validasi materi memperoleh persentase sebesar 87% sehingga e-modul dikategorikan sangat valid. Kemudian hasil validasi media memperoleh persentase sebesar 81% sehingga e-modul dikategorikan sangat valid. Selanjutnya yaitu uji kepraktisan yang dilakukan oleh guru dan siswa. Hasil uji kepraktisan menggunakan angket memperoleh persentase dari guru sebesar 97% menunjukkan e-modul sangat praktis, sedangkan persentase dari siswa sebesar 95% dengan kategori sangat praktis. Hal ini menunjukkan bahwa e-modul yang telah dikembangkan dikategorikan sangat praktis. Hasil uji N-gain memperoleh nilai rata-rata sebesar 0,71 yang dikategorikan tinggi. Saran untuk peneliti selanjutnya, pengembangan e-modul diharapkan tidak hanya terbatas pada materi transformasi geometri kelas IX, tetapi dapat dikembangkan dalam materi atau jenjang lainnya. Selain itu, uji coba juga dapat diperluas cakupan subjek dan indikator kemampuan matematis lainnya.
Kata Kunci: Demos, E-Modul Flipbook, Kemampuan Pemecahan Masalah Matematis, PjBL, Transformasi Geometri.

Mathematical problem solving skills are very important for students to have, but in reality, students' problem solving skills are still low because many students still have difficulty solving problems in the form of story problems such as geometric transformation problems. This is due to the lack of teaching materials that support student learning, so teaching materials are needed to help improve students' mathematical problem solving skills. This study aims to develop a flipbook e-module using PjBL syntax that can support student learning in improving mathematical problem solving skills in geometric transformation material. The type of research used in this study is research and development or Research and Development (R&D) which uses the ADDIE development model, namely Analysis, Design, Development, Implementation, and Evaluation. The subjects used in the study were 26 class IX A students at SMP Negeri 1 Hantara. Data collection techniques used questionnaires, interviews, and tests. The instruments used in this study were validation sheets, practicality questionnaire sheets, test description questions, and interview guidelines. Data sources were obtained from lecturers, teachers, and students. The e-module product was tested for validity by expert validators in the material and media. The results of the material validation obtained a percentage of 87% so that the e-module was categorized as very valid. Then the results of the media validation obtained a percentage of 81% so that the e-module was categorized as very valid. Next is the practicality test carried out by teachers and students. The results of the practicality test using a questionnaire obtained a percentage from teachers of 97% indicating that the e-module was very practical, while the percentage from students was 95% with a very practical category. This shows that the e-module that has been developed is categorized as very practical. The results of the N-gain test obtained an average value of 0.71 which is categorized as high. Suggestions for further researchers, the development of e-modules is expected not only to be limited to grade IX geometric transformation material, but can be developed in other materials or levels. In addition, the trial can also be expanded to include other subjects and indicators of mathematical ability.
Keywords: Demos, Flipbook E-Module, Mathematical Problem-Solving Ability, PjBL, Geometric Transformation.