PENGEMBANGAN BAHAN AJAR MATEMATIKA BERDIFERENSIASI DENGAN PENDEKATAN PROJECT-BASED LEARNING (PjBL) UNTUK MENINGKATKAN KETERLIBATAN SISWA DALAM PEMECAHAN MASALAH DI SMP

The development of differentiated mathematics teaching materials using the Project-Based Learning (PjBL) approach plays an important role in enhancing students’ engagement and their problem-solving abilities. This innovation is expected to serve as a solution that bridges the gap between the ideals promoted by the Merdeka Curriculum and the realities of classroom learning, making the learning process more meaningful, active, and responsive to students’ needs. This study aims to: (1) determine the validity level of differentiated mathematics teaching materials based on the Project-Based Learning (PjBL) approach, and (2) assess the level of student engagement in problem-solving after using the materials. The development model used is ADDIE, which consists of five stages: Analysis, Design, Development, Implementation, and Evaluation. The research subjects were 30 eighth-grade students at SMP Negeri H. Wukirsari during the second semester of the 2024/2025 academic year. Data were collected qualitatively through expert validation sheets and student engagement questionnaires. The results of the study indicate that: (1) the differentiated mathematics teaching materials based on PjBL have a very high level of validity according to assessments from experts in content, media, and learning, covering aspects of content, presentation, language, and visual design; and (2) the materials proved effective in increasing student engagement cognitively, affectively, and behaviorally. Students appeared more active in discussions, enthusiastic in completing projects, and demonstrated improved critical and collaborative thinking skills