Journal of Didactic Mathematics 2023, 4(1), 24-35 Doi: 10.34007/jdm.v4i1.1730 https://mahesainstitute.web.id/ojs2/index.php/jdm journalofdidacticmathematics@gmail.com Journal of Didactic Mathematics 24 Belajar dan berkuliner materi aritmetika sosial melalui kegiatan jual beli jajanan tradisional dumbeg Adi Satrio Ardiansyah* Universiitas Negeri Semarang, Kota Semarang, Jawa Tengah, Indonesia, 50229 Adistia Nia Safitri Universiitas Negeri Semarang, Kota Semarang, Jawa Tengah, Indonesia, 50229 Anisa Firdaus Oktaviani Universiitas Negeri Semarang, Kota Semarang, Jawa Tengah, Indonesia, 50229 *Corresponding Author: adisatrio@mail.unnes.ac.id Abstract. The assumption that mathematics is a difficult and boring subject result in students' lack of understanding of the mathematics. Lack of teacher creativity in carrying out learning is also considered as one of the causes of these problems. There needs to be innovation in learning mathematics such as the development of innovative teaching materials and in accordance with the characteristics of students. This study aims to develop teaching materials for social arithmetic with Ethnomatematics nuances on Dumbeg objects. Development research with a 4D model that is adjusted to 3D is carried out by paying attention to each stage from define, design, to develop. The data in the study were obtained through interviews, ethnographic notes, and questionnaires which were then analyzed descriptively quantitatively to obtain prototypes of teaching materials that were appropriate, easy to understand, and had a good response to students. The results of the study show that teaching materials are appropriate, easy to understand, and have a good response to students. The feasibility of teaching materials can be seen from the final scores by experts and practitioners of 82.93% and 90.67%, respectively. The readability of teaching materials can be seen from the final score of the readers of 89%. Student responses can be seen from the final score of 95%. Thus, the developed prototype is ready to be implemented in class. Historis Artikel: Diterima: 05 Maret 2023 Direvisi: 18 Maret 2023 Disetujui: 26 April 2023 Keywords: Social arithmetics; teaching materials; dumbeg; ethnomatematics Sitasi: Ardiansyah, A. S., Safitri, A. N., & Oktaviani, A. F. (2023). Belajar dan berkuliner materi aritmetika sosial melalui kegiatan jual beli jajanan tradisional dumbeg. Journal of Didactic Mathematics, 4(1), 24-35. Doi: 10.34007/jdm.v4i1.1730 PENDAHULUAN Pendidikan dan kebudayaan merupakan satu kesatuan yang tidak dapat dipisahkan dalam kehidupan sehari-hari. Hal ini membuat pendidikan dan budaya berperan penting dalam mengembangkan nilai-nilai luhur suatu bangsa yang berdampak pada pembentukan karakter manusia (Wahyuni et al., 2013). Pembentukan karakter dapat dilakukan melalui proses pembelajaran di kelas. Matematika sebagai salah satu pelajaran yang selalu hadir pada setiap jenjang pendidikan di Indonesia mulai dari sekolah dasar hingga sekolah menengah tidak hanya mempelajari konten matematika, tetapi bagaimana matematika dapat mengembangkan nilai-nilai matematisnya. Lebih lanjut, Cockcroft (1986) mengemukakan beberapa alasan pentingnya pembelajaran matematika, yaitu matematika selalu digunakan dalam semua aspek kehidupan dimana semua bidang penelitian membutuhkan keterampilan matematika; matematika adalah alat komunikasi yang kuat, ringkas, dan jelas; matematika dapat digunakan untuk menyajikan data dalam berbagai metode; matematika meningkatkan keterampilan berpikir logis, akurasi, dan