Effectiveness of the Contextual Teaching and Learning (CTL) Model Assisted by GeoGebra on Vocational High School Students’ Mathematical Critical Thinking Skills

Abstract

This study aimed to analyze the effectiveness of the Contextual Teaching and Learning (CTL) model assisted by GeoGebra in improving vocational high school students’ mathematical critical thinking skills. The study was motivated by the low level of students’ mathematical critical thinking skills caused by teacher-centered learning practices and the limited use of interactive learning media in mathematics instruction. This research employed a quantitative approach using a quasi-experimental method with a pretest-posttest control group design. The sample consisted of 60 eleventh-grade vocational high school students divided into an experimental class and a control class through purposive sampling techniques. The research instrument was an essay-based mathematical critical thinking test that had met validity and reliability requirements. Data were analyzed using descriptive and inferential statistics, including normality tests, homogeneity tests, independent sample t-tests, and N-Gain analysis with the assistance of IBM SPSS Statistics version 26. The results showed that the posttest mean score of the experimental class was higher than that of the control class. Furthermore, the t-test analysis revealed a significance value of 0.000 < 0.05, indicating a significant effect of the CTL model assisted by GeoGebra on students’ mathematical critical thinking skills. The N-Gain score of the experimental class was also categorized as high. Therefore, the CTL model assisted by GeoGebra was proven effective in improving vocational high school students’ mathematical critical thinking skills. This study contributes to the development of technology-based and contextual mathematics learning to support 21st-century education.