Penerapan Model Problem Based Learning Melalui Aktivitas Class of Champion Untuk Meningkatkan Kemampuan Berpikir Kritis Dan Tanggung Jawab Murid Kelas Iii Pada Materi Keberagaman Budaya Indonesia

Objective: This study describes the implementation of Problem Based Learning through Class of Champion activities to improve critical thinking and responsibility of grade III students on Indonesian Cultural Diversity. Methods: This Classroom Action Research used the Kemmis and McTaggart model in two cycles with 28 students. Data were collected through critical thinking tests and responsibility observation sheets, then analyzed descriptively and quantitatively. Results: Critical thinking increased from 69.64 (28.6% mastery) in pre-cycle to 73.57 (64.29%) in Cycle I and 85.54 (100%) in Cycle II. Responsibility improved from 77.32 (25% needing guidance) to 85.18 (7.14%) in Cycle I and 90.54 (100% very good) in Cycle II. Novelty: Integrating gamification-based Class of Champion into PBL syntax creates structured group competition that simultaneously develops critical thinking and responsibility through clear roles within the group.