This study analyzes the presentation of area concepts for triangles and quadrilaterals in Indonesian and Japanese textbooks using the praxeology framework and evaluates potential learning obstacles through Didactical Design Research. The Indonesian textbook offers broader task variations but relies on limited techniques, which may potentially lead to ontogenic, didactic, and epistemological obstacles. Conversely, the Japanese textbook incorporates more comprehensive techniques, emphasizing a universal triangle-based approach and Euclidean geometry, yet excludes the area of kites, which may cause potential didactic obstacles. The findings highlight the need for educators to critically select textbooks and for policymakers to develop materials that address diverse learning needs while minimizing obstacles. This research offers valuable insights for improving mathematics education by aligning textbook content with pedagogical goals and student contexts.
Muhaimin et al. (Tue,) studied this question.