Cognitive Transition in PMRI: Challenges and the Need for Scaffolding

Indonesian Realistic Mathematics Education (PMRI) enables students to begin mathematical learning from meaningful contextual situations and progressively reconstruct formal mathematical knowledge. While previous studies have documented success in contextualization, informal modeling, and progressive mathematization, the transition from model-for reasoning toward formal mathematical understanding remains underexplored. This narrative and critical literature review examined 40 articles published between 2021 and 2026, identified through Scopus, Google Scholar, and snowballing from reference lists of highly relevant studies. Thematic synthesis revealed three recurring challenges clustering at a single vulnerable point in the learning trajectory: cognitive fragmentation, incomplete abstraction, and formalization difficulty. This review conceptualizes that point as the Critical Transition Zone—located between model-for reasoning and formal mathematical understanding. Scaffolding positioned within this zone functions as a cognitive bridge, supporting students in coordinating representations, generalizing mathematical structures, and constructing formal understanding without displacing their own mathematical reasoning.