PjBL Berbasis Etnomatematika Mardalan untuk Pemahaman Geometri dan Pengukuran Siswa Sekolah Dasar

Abstract

Low achievement in geometry and measurement at the elementary level is often associated with instruction that is detached from students’ context. This study examined an ethnomathematics-based Project-Based Learning (PjBL) model built on the Mardalan activity and its relationship with students’ conceptual understanding of geometry and measurement. An explanatory sequential mixed-methods design was used. The quantitative phase applied a quasi-experimental pretest-posttest control group design with 64 fifth-grade students in Sigalapang Julu, and the qualitative phase involved fidelity observations, project artifact analysis, and interviews with six students selected by ability level. After controlling for pre-test scores, the experimental group obtained significantly higher post-test scores than the control group ( ) with a large effect size ( ). Integration of both data sets indicated that measuring the Mardalan route with non-standard units, comparing them with standard units, and decomposing irregular areas during the project help explain the experimental group’s higher performance on unit conversion and composite area items. The role of project artifacts differed by ability level. The findings support the use of local cultural practices as a basis for classroom intervention, although generalization is limited to a single-school context.