<![CDATA[This study focuses on examining the use of PDF-format textbooks to enhance the thinking skills of Grade XI students in the Arabic language subject at MAN Batubara. A quantitative approach with a quasi-experimental design specifically a one-group pretest-posttest framework was employed. Thirty-two Grade XI students from MAN Batubara participated in the study. Data were collected through cognitive tests administered before (pretest) and after (posttest) the use of the PDF-based textbook, as well as through documentation to corroborate observational data. Data analysis utilized descriptive statistics, a paired-sample t-test, and the normalized gain (N-Gain) test. The results indicate that the students' average score rose from 70.16 on the pretest to 79.53 on the posttest. The paired-sample t-test yielded a significance value of 0.000 (p < 0.05) with an effect size (Cohen's d) of 0.878 categorized as a large effect demonstrating a significant difference in students' cognitive abilities before and after the implementation of the PDF-based textbook. However, the N-Gain analysis showed an average score of 0.27, falling into the low category, which indicates that the improvement in students' cognitive abilities was not yet optimal. Thus, while PDF-based textbooks offer a flexible and accessible learning resource for Arabic language instruction, incorporating multimedia elements and interactive activities is necessary to maximize their effectiveness in enhancing students' cognitive abilities.]]>
