Efektivitas Pembelajaran Matematika Berbasis Problem Solving terhadap Keterampilan Berpikir Kritis Siswa Sekolah Dasar

This study aimed to analyze the effectiveness of mathematics learning based on problem solving in improving elementary school students' critical thinking skills. The descriptive quantitative study used a one-group pretest-posttest design in two classes without a control group. The sample comprised 73 fifth-grade students consisting of class 5A with 36 students and class 5B with 37 students. Data were collected through observation sheets, document analysis of lesson plans and worksheets, critical thinking tests, teacher questionnaires, and semi-structured interviews. The data were analyzed descriptively using percentages, mean scores, category shifts, absolute gain, and normalized gain. The results showed that the implementation of problem-solving learning was categorized as good to high, although the quality varied between teachers. Students' critical thinking skills increased after the intervention. In class 5A, the mean score increased from 53.38 to 69.24, with an absolute gain of 15.86 and a normalized gain of 0.288. In class 5B, the mean score increased from 49.53 to 67.13, with an absolute gain of 17.60 and a normalized gain of 0.326. The category distribution also shifted positively: no students remained in the low category, and several students reached the very high category. The findings indicate that problem-solving-based mathematics learning is effective at a moderate level and contributes positively to the development of students' analytical, reflective, and argumentative thinking.