<![CDATA[This study investigated the effectiveness of the Problem-Based Learning (PBL) model in improving Grade XI students’ conceptual understanding of temperature and heat at SMA Negeri 4 Ketapang. A quasi-experimental method with a pre-test - post-test control group design was employed involving 50 students, consisting of 25 students in the experimental class and 25 in the control class. The classes were selected through purposive sampling based on comparable class size and academic ability. Students’ conceptual understanding was measured using multiple-choice tests administered before and after instruction. The experimental class received instruction using the PBL model, while the control class was taught through conventional instruction. The results showed that the mean pretest and posttest scores of the experimental class increased from 48.20 to 84.20, whereas those of the control class increased from 46.50 to 65.40. The experimental class achieved an N-gain score of 0.72, categorized as high, while the control class obtained 0.35, categorized as medium. The Wilcoxon test indicated a significant difference between pretest and post-test scores in both classes (p < 0.05). Furthermore, the Mann–Whitney test revealed a significant difference in N-gain scores between the experimental and control classes (p < 0.05). These findings indicate that PBL was more effective than conventional instruction in enhancing students’ conceptual understanding of temperature and heat. The findings highlight the potential of PBL to promote deeper conceptual understanding through problem-oriented physics learning.]]>
