The Effectiveness of Differentiated Instruction with a Realistic Mathematics Education (RME) Approach in Terms of Mathematical Literacy and Self-efficacy of Junior High School Students on the Topic of Systems of Linear Equations in Two Variables

Abstract

The purpose of this study is to describe the effectiveness of differentiated instruction using the Realistic Mathematics Education (RME) approach in terms of students’ mathematical literacy and self-efficacy in two experimental classes: experimental class 1 (slow learners) and experimental class 2 (fast learners). Additionally, this study aims to identify which class demonstrates greater effectiveness in implementing differentiated instruction with the RME approach. In this study, differentiated instruction was applied by grouping students based on their interests, while the RME approach was used to design the mathematics learning activities in class. This study employed a quasi-experimental method with a non-equivalent pretest-posttest group design. The research was conducted at private junior high school in Sleman between January and February 2025. The population consisted of all eighth-grade students at the school during the second semester of the 2024/2025 academic year. The classes were selected based on the research objective—to compare slow learners and fast learners—as well as recommendations from the school's mathematics teacher. The selected sample consisted of class VIII A (slow learners) as experimental class 1 and class VIII C (fast learners) as experimental class 2. Data collection instruments included lesson implementation observation sheets, pretests and posttests for mathematical literacy, and a student self-efficacy questionnaire. Prior to implementation, all instruments were tested in a class not included in the main study. The results indicated that all instruments were valid and reliable, meaning they were suitable for use in this research. The statistical analyses used included Pillai’s Trace test to determine differences in the mean vectors between two independent samples, followed by an independent samples t-test. The results of the study showed that the implementation of differentiated instruction with the RME approach in experimental class 1 was not effective in terms of students’ mathematical literacy, but it was effective in terms of self-efficacy. In contrast, in experimental class 2, the implementation was effective in terms of both mathematical literacy and self-efficacy. Furthermore, the study indicated that differentiated instruction with the RME approach was more effective when implemented in the fast learner class (experimental class 2) compared to the slow learner class (experimental class 1), in terms of both mathematical literacy and self-efficacy. Future research is recommended to explore other types of differentiation and different student characteristics to broaden the scope of differentiated instruction implementation.