<![CDATA[The observations indicate that mathematics learning processes that rely heavily on providing practical and procedural formulas tend to hinder the development of students’ critical thinking skills. Critical thinking is an essential competency for analyzing information, evaluating arguments, and making rational decisions; therefore, it is necessary for understanding higher-level mathematical concepts. This condition contributes to the low mathematical thinking ability of students, particularly in topics requiring analytical skills such as differential equations. This study aims to determine the improvement of students’ mathematical critical thinking skills through the implementation of the RCODE Learning Model among students of the DIII Electronics Engineering Program. This quantitative research involved 21 students from class IB in the even semester of the 2024/2025 academic year, focusing on second-order differential equations. Data were collected through mathematical critical thinking skill tests, response questionnaires, and interviews to support the quantitative findings. Data were analyzed using SPSS through normality tests, homogeneity tests, proportion tests, and N-gain calculations. The results show that the students’ achievement of the Minimum Mastery Criteria (KKM 67) was met both individually and classically, with a classical completeness percentage of 75%. The improvement in students’ Mathematical Critical Thinking Skills (MCTS) after the implementation of RCODE learning resulted in an N-gain value of 0.47, which falls into the moderate improvement category. The average MCTS score reached 8.19 on a 0–10 scale. More specifically, the problem understanding aspect (interpretation) obtained an average score of 8.55; the planning or modeling aspect (analysis) scored 8.26; the implementation and calculation aspect (evaluation) scored 7.92; and the conclusion-drawing aspect (inference) scored 8.03. These findings show that the RCODE learning model positively contributes to improving students’ MCTS, particularly in helping them understand concepts, analyze strategies, and evaluate solutions in second-order differential equation topics.]]>
