Skripsi
KEMAMPUAN PENALARAN MATEMATIS SISWA KELAS X PADA MATERI BARISAN ARITMETIKA MELALUI MODEL CONTEXTUAL TEACHING AND LEARNING
This study aims to describe students’ mathematical reasoning abilities through the implementation of the Contextual Teaching and Learning (CTL) instructional model in the topic of arithmetic sequences. The study employed a descriptive qualitative research design. The participants consisted of 33 tenth-grade students from class X.A at SMA Pusri Palembang. Six students were selected as key informants using purposive sampling based on test result, teacher recommendation, and student readiness. Those informants classified into high-, medium-, and low-ability categories. Data were collected through classroom observations, written mathematical reasoning tests, and interviews. Data analysis followed the stages of data reduction, data display, and conclusion drawing. The findings indicate that students’ mathematical reasoning abilities varied across indicators, as reflected in differences among the three ability categories. Students in the high-ability category were able to represent mathematical statements, perform mathematical manipulations, construct proofs or provide justifications for the correctness of solutions, and draw conclusions. Students in the medium-ability category were able to represent mathematical statements and identify patterns but were not yet consistent in performing mathematical manipulations and drawing logical conclusions. In contrast, students in the low-ability category experienced difficulties in understanding problem contexts and relating them to mathematical concepts. The implementation of the CTL model supported students’ engagement and reasoning processes, although challenges related to time constraints and varying levels of participation remained. These findings suggest the need for improved instructional time management and targeted learning support.