<![CDATA[Early childhood critical thinking skills often remain below expected developmental standards due to learning practices that rely on conventional teacher-centered approaches. This study aims to examine the effectiveness of an integrated Science, Technology, Engineering, Arts, and Mathematics (STEAM) approach combined with PBL in improving critical thinking skills in 4–5-year-old children. A quantitative method with a quasi-experimental non-equivalent control group design was used. The study subjects consisted of 20 children divided into an experimental group and a control group. Data were collected through structured observation sheets. Data analysis used descriptive and inferential statistics and normalized gain (N-gain) analysis to measure the level of improvement. The results showed that both groups experienced improvements in critical thinking skills, but the improvement in the experimental group was significantly higher. The experimental group showed moderate to high N-gain improvements, while the control group showed low improvements. Statistical tests also showed significant differences between pretest and posttest scores and between groups. These findings suggest that integrating STEAM with project-based learning provides meaningful learning experiences that support children's active engagement, inquiry, and reasoning processes. In conclusion, the STEAM PBL approach is effective in improving critical thinking skills in early childhood. This study suggests that interdisciplinary and project-oriented learning can serve as alternative instructional strategies for fostering higher-order thinking and active learning in early childhood education.]]>
