<![CDATA[Creative thinking and intrinsic motivation remain insufficiently developed in Indonesian junior high school mathematics, as reflected in students’ low performance in the PISA 2022 mathematics and creative-thinking domains. This development research, adapted from Plomp’s model, comprised preliminary research, prototyping, and assessment phases. It aimed to design, validate, and evaluate a Contextual Teaching and Learning (CTL)-based Social Arithmetic module for fostering seventh-grade students’ creative thinking and intrinsic motivation. Formative evaluation included a one-to-one evaluation with three students, a small-group trial with six students, and a field test involving 28 heterogeneous seventh-grade students at SMP Avava Batam. Data were collected using expert validation sheets, classroom observations, student and teacher response questionnaires, a pretest–posttest creative-thinking test, and an intrinsic-motivation questionnaire. Aiken’s V was used to assess validity, while practicality and learning improvements were analyzed descriptively and through normalized gain. The module was valid, achieving mean validity scores of 71.11% for media, 77.08% for content, and 72.92% for language. It was also practical to very practical, receiving positive responses of 80.51% from students and 70.00% from the teacher. Students’ creative-thinking scores increased, particularly in originality, while intrinsic motivation achieved a medium N-gain of 0.46. However, because the field test used a one-group pretest–posttest design without inferential analysis, the results indicate descriptive improvement rather than causality. Further studies should confirm these findings through controlled designs, inferential testing, and larger, more diverse samples across schools and regions.]]>
