The Effect of Differentiated Learning with the STAD Cooperative Learning Model on Mathematical Problem-Solving Skills and Self-Confidence of Students in Inclusive Classrooms

Abstract

This study aims to describe the effect of differentiated learning using the STAD cooperative learning model on mathematical problem-solving skills and student confidence in inclusive classrooms, as well as to describe the advantages of differentiated learning using the STAD cooperative learning model compared to differentiated learning using the expository model in terms of a) mathematical problem-solving skills; and b) students' self-confidence in inclusive classrooms. The research used a quasi-experimental method with a nonequivalent control group design. The research population consisted of all 10th grade students at MA Negeri 2 Sleman in the 2024/2025 academic year. The sampling technique used was cluster random sampling, consisting of 35 students from class X D as the experimental group who received differentiated learning with the STAD model, and 34 students from class X C as the control group with the expository model. Data were collected using a mathematical problem-solving ability test and a self-confidence questionnaire. The instruments were validated through content validity (expert judgment) and declared reliable with Cronbach's Alpha coefficient. Data analysis used Hotelling's T2 Test and Independent Sample t-Test at a significance level of ???? = 0.05. The results of the study show that: (1) differentiated learning with the STAD model has a significant effect on students' mathematical problem-solving abilities and self-confidence in inclusive classrooms; (2) the STAD model is significantly superior to the expository model in improving these two variables. These findings indicate that the integration of differentiated learning with the STAD model is effective when applied in inclusive classrooms to optimize students' cognitive and affective abilities.