PENERAPAN PROBLEM BASED LEARNING PADA MATERI PENCEMARAN LINGKUNGAN UNTUK MENINGKATKAN KEMAMPUAN BERPIKIR KRITIS SISWA

APPLICATION OF PROBLEM BASED LEARNING ON ENVIRONMENTAL POLLUTION TO IMPROVE STUDENT CRITICAL THINKING ABILITIES

Penelitian ini bertujuan untuk mengetahui keterlaksanaan pembelajaran, peningkatan kemampuan berpikir kritis siswa, serta respons siswa terhadap penerapan model Problem Based Learning (PBL) pada materi pencemaran lingkungan di kelas VII. Latar belakang penelitian ini didasarkan pada rendahnya kemampuan berpikir kritis siswa Indonesia berdasarkan studi PISA, serta kebutuhan pembelajaran abad ke-21 yang menuntut pengembangan keterampilan berpikir tingkat tinggi. Jenis penelitian yang digunakan adalah quasi experiment dengan desain nonequivalent control group design. Sampel penelitian terdiri dari dua kelas VII di UPT SMPN 9 Gresik yang dipilih secara purposive sampling. Instrumen yang digunakan meliputi lembar observasi keterlaksanaan pembelajaran, tes pretest dan posttest kemampuan berpikir kritis, serta angket respons siswa. Hasil penelitian menunjukkan bahwa keterlaksanaan pembelajaran dengan model PBL mencapai persentase 93,18% yang dikategorikan “Sangat Baik”. Hasil uji paired t-test menunjukkan adanya peningkatan signifikan kemampuan berpikir kritis siswa baik pada kelas eksperimen (selisih 12,45; p < 0,05) maupun kontrol (selisih 9,03; p < 0,05). Rata-rata nilai N-Gain kelas eksperimen sebesar 0,3101 (kategori sedang), sedangkan kelas kontrol sebesar 0,2106 (kategori rendah). Uji One-Way ANCOVA menunjukkan signifikansi 0,058 dengan effect size sebesar 0,060 yang termasuk kategori sedang. Hasil angket menunjukkan bahwa respons siswa terhadap penerapan model PBL berada pada kategori “Sangat Baik” dengan rata-rata persentase 77,72%. Dapat disimpulkan bahwa model Problem Based Learning efektif dalam meningkatkan kemampuan berpikir kritis siswa serta diterima dengan baik oleh siswa pada pembelajaran IPA materi pencemaran lingkungan.

Kata kunci: Problem Based Learning, Kemampuan Berpikir Kritis, Pencemaran Lingkungan

This study aims to determine the implementation of learning, the improvement of students’ critical thinking skills, and students' responses to the application of the Problem-Based Learning (PBL) model on environmental pollution material in grade VII. The background of this research is based on the low level of Indonesian students’ critical thinking skills as revealed in the PISA study, as well as the demands of 21st-century learning, which emphasize the development of higher-order thinking skills. This research used a quasi-experimental method with a nonequivalent control group design. The sample consisted of two grade VII classes at UPT SMPN 9 Gresik, selected through purposive sampling. Instruments used include observation sheets for learning implementation, pretest and posttest critical thinking tests, and student response questionnaires. The results showed that the implementation of PBL reached a percentage of 93.18%, categorized as “Very Good”. The paired t-test showed a significant increase in critical thinking skills in both the experimental class (difference of 12.45; p < 0.05) and the control class (difference of 9.03; p < 0.05). The average N-Gain score in the experimental class was 0.3101 (moderate category), while in the control class it was 0.2106 (low category). The One-Way ANCOVA test yielded a significance value of 0.058 with an effect size of 0.060, which is categorized as moderate. Student responses toward the implementation of PBL were also very positive, with an average percentage of 77.72%. It can be concluded that the Problem-Based Learning model is effective in improving students’ critical thinking skills and is well-received in science learning on environmental pollution material.

Keywords: Problem-Based Learning, Critical Thinking Skills, Environmental Pollution