Analisis Kemampuan Berpikir Kritis Siswa Pada Materi Relasi Dan Fungsi Di Kelasviii SMP Swasta Teladan Pematangsiantar

This study describes the critical thinking profile of eighth-grade students on relations and functions and identifies their difficulties across four indicators: interpretation, analysis, evaluation, and inference. A descriptive qualitative study involved 29 students of class VIII-B at SMP Swasta Teladan Pematangsiantar. Students completed a four-item essay test, with one item per indicator, scored on a 0–4 analytic rubric (Cronbach’s alpha = 0.749). Six students from high, medium, and low categories were interviewed, and test and interview data were triangulated and analyzed through data reduction, data display, and conclusion drawing. Average achievement was 66.81%, highest in interpretation (71.55%) and lowest in analysis (62.07%). Analysis was the most polarized indicator: 14 students obtained full scores, whereas 14 others scored 1. Students were distributed into high (48.28%), medium (6.90%), and low (44.83%) categories. Interviews revealed that low-category students had not yet understood all problem information, and medium-category students who obtained full scores on evaluation and inference remained unsure whether their answers met the conditions of a function. This study maps students’ difficulties on each critical thinking indicator using one item per indicator, compares them across ability categories, and checks written scores against oral explanations. The triangulation shows that full written scores may not always reflect the reasoning behind them.