Transforming Geometric Thinking Through a Flipped Semi-Concrete Model: A Van Hiele and Cognitive Load Theory Perspective in Coastal Elementary Education

Abstract

Geometric learning among coastal elementary students in Indonesia is often constrained by limited access to learning resources and difficulties in visualizing three-dimensional concepts. Grounded in Van Hiele theory and Cognitive Load Theory, this study examined the effectiveness of the Flipped Semi-Concrete Geometry Model (FSC-GM), which integrates flipped learning with locally sourced semi-concrete media from coastal contexts. Using a sequential explanatory mixed-methods design, the study involved 19 fifth-grade students in a coastal elementary school in Cirebon Regency. Quantitative data were analyzed using one-sample t-tests and correlation analysis, followed by qualitative content analysis of student interviews and classroom observations. The results showed that students' geometric thinking scores significantly exceeded the minimum mastery criterion (KKM = 60) following the intervention (t = 3.269, p < 0.05, d = 0.76), indicating a medium-to-large practical effect, while self-efficacy gains were not statistically significant (t = 1.143, p = 0.268) and exhibited a weak correlation with geometric thinking (r = 0.237). Qualitative findings revealed that the use of semi-concrete coastal objects reduced extraneous cognitive load, supported students’ progression across Van Hiele levels, and enabled meaningful connections between geometry and everyday coastal experiences. The findings suggest that cognitive and affective outcomes follow distinct developmental trajectories, highlighting the need for sustained and culturally responsive instructional approaches in coastal and resource-limited contexts.