Voice-Interactive 2D Serious Game with Three-Tier Scaffolding for Teaching Acoustics in Primary Schools: A Randomized Comparison of Knowledge, Motivation, and Cognitive Load

Misconceptions about sound are common among primary-school pupils, but research on voice-interactive game-based learning remains limited, especially regarding the role of scaffolding. We investigated whether a voice-interactive 2D platformer with a three-tier scaffolding model improves learning about loudness, pitch, and echo. In a classroom-feasible randomized comparison, 45 third-graders were assigned to a scaffolded serious game (SSG), a non-scaffolded serious game (NSG), or traditional hands-on materials instruction (TRAD) on matched sound content. Outcomes were an immediate eight-item knowledge test and learner-centered ratings of perceived learning, flow, intrinsic motivation, and extraneous cognitive load (ECL). The knowledge test showed low internal consistency, so results involving this measure should be interpreted with caution. SSG yielded higher immediate learning than NSG and matched traditional instruction. Across experience measures, only intrinsic motivation differed, favoring NSG. Hierarchical regression revealed a motivation-by-structure effect: scaffolding strengthened the positive association between intrinsic motivation and test scores, whereas ECL was not predictive. Findings indicate that voice-interactive serious games can match near-term learning achieved with physical materials, and well-calibrated scaffolds help convert motivation into accurate encoding. We also map sound constructs to gameplay mechanics and provide a compact, classroom-feasible, replicable evaluation design for primary classrooms.