Development of RADEC-Based Deep Learning Lesson Planning to Enhance Fifth-Grade Students’ Critical Thinking Skills in Integrated Science and Social Studies

Abstract

Critical thinking is an essential 21st-century competency, yet its development in elementary education is often constrained by instructional planning that provides limited opportunities for higher-order thinking. This study developed and evaluated RADEC-based Deep Learning Lesson Planning integrating the Read, Answer, Discuss, Explain, and Create stages to support fifth-grade students’ critical-thinking skills in Integrated Science and Social Studies (IPAS). Using a Research and Development approach with the ADDIE model, the study involved product development, expert validation, teacher evaluation, and limited implementation with 23 fifth-grade students in Bandung Regency during the 2025/2026 academic year. Data were collected through expert-validation instruments, a teacher-response questionnaire, and critical-thinking pretest and posttest assessments. Expert validation yielded scores of 90% for language and 95% for both subject matter and instructional design, while the teacher evaluation reached 92.85%, indicating high product feasibility and practicality. Students’ mean critical-thinking score increased from 54.22 to 80.22, with a significant pretest–posttest difference, t(22) = −10.552, p < .001, and a mean N-Gain of 0.5605, representing moderate improvement. These findings provide preliminary evidence that the developed lesson planning is valid, practical, and associated with improved critical-thinking performance in IPAS. Further controlled studies with larger and more diverse samples are needed to establish its effectiveness and broader applicability.