Promoting primary students' critical thinking via an optimized SDOA model: A cross-cultural study in China and Thailand

This study examines whether an optimized Selection–Design–Organization–Assessment (SDOA) instructional model cultivates primary students' critical thinking (CT) and transfers across cultures. Using a quasi-experimental mixed-methods design, 145 fourth-graders in China and Thailand were assigned to SDOA or conventional instruction over 20 weeks. The enhanced SDOA aligned activities and reflection prompts with Gelerstein's six CT domains (Memory, Comprehension, Analysis, Evaluation, Inference, Reflective Judgment). ANCOVA controlling for pretest showed significant treatment effects on total CT, with large gains concentrated in Memory, Analysis, and Reflective Judgment; Evaluation and Inference improved modestly, indicating a need for more targeted scaffolds. Two-way ANOVA/ANCOVA detected no main effect of country and no interaction, demonstrating cross-cultural applicability. Interview data corroborated quantitative patterns, revealing stronger meta-cognitive awareness, evidence use, and peer-regulated reasoning in experimental classrooms. Theoretically, the model integrates cognitive scaffolding with learner agency; practically, it offers a feasible, culturally adaptable design for early-grade mathematics that can be extended to other subjects. Implications include embedding argument mapping and evidence-chain tasks to strengthen higher-order evaluation and inference. • An optimized SDOA model was developed to foster critical thinking in primary education. • The study applied a cross-cultural design involving students from China and Thailand. • Significant improvements were found in Memory, Analysis, and Reflective Judgment domains. • Structured reflection and peer feedback were key to enhancing meta-cognitive skills. • Findings offer a culturally adaptable instructional approach for early critical thinking development.