Experimentation of Problem-Based Learning Model on Critical Thinking Ability in Learning Number Theory

Abstract
Critical thinking is needed in learning mathematics because it can train students to develop and analyze problems given. The research aims to determine the effect of PBL models on critical thinking skills in learning number theory. The research experimental design used was the one-group pretest-posttest. The subjects of this research are students of the Mathematics Education Muhammadiyah University of Metro who had taken the learning number theory. The instrument in this research was a critical thinking test. Data analysis techniques used in this research were (1) normality test using the Liliefors test, (2) homogeneity test using Bartlet test, and (3) hypothesis testing using paired mean difference test. Based on the results of data analysis, it can be concluded that: (1) There is an effect of PBL model on students' critical thinking skills, (2) There is a difference in the average N-Gain score of students' critical thinking skills before and after using PBL with observed = 12,025 > tcritical (0.05; 1) = 2,001., (3) PBL can increase in the average value proportion of each indicator of critical thinking.