摘要：Hasil belajar yang kurang maksimal menunjukkan kemampuan berpikir kritis siswa yang kurang maksimal pula.Salah satu model pembelajaran yang dapat meningkatkan kemampuan berpikir kritis siswa adalah problem based learning.Tujuan penelitian ini untuk mengetahui pengaruh model problem based learning terhadap kemampuan berpikir kritis siswa pada materi sistem ekskresi.Sampel yang digunakan adalah kelas XI IPA 1 sebagai kelas eksperimen dan kelas XI IPA 2 sebagai kelas kontrol.Penelitian quasi eksperimental ini menggunakan posttest only control design.Variabel yang diukur adalah kemampuan berpikir kritis siswa yang diperoleh dari skor posttest yang diuji korelasi biserial dan uji-t.Aktivitas siswa,tanggapan siswa,dan tanggapan guru dianalisis menggunakan analisis deskriptif kualitatif persentase.Berdasarkan hasil penelitian,rata-rata skor kemampuan berpikir kritis kelas eksperimen adalah 76,93 sedangkan kontrol adalah 65,67.Hasil uji-t menunjukkan bahwa terdapat pengaruh yang signifikan antara pembelajaran biologi model Problem Based Learning terhadap kemampuan berpikir kritis siswa di SMAN 1 Singorojo.Hasil uji korelasi biserial menunjukkan bahwa pembelajaran biologi model Problem Based Learning memiliki hubungan yang kuat terhadap kemampuan berpikir kritis siswa.Analisis aktivitas siswa secara deskriptif menunjukkan bahwa kelas ekskperimen lebih tinggi dibandingkan kelas kontrol.Simpulan dari penelitian ini adalah pembelajaran biologi model problem based learning berpengaruh meningkatkan kemampuan berpikir kritis siswa.
其他摘要：Students’ achievement which is not maximal can show that their critical thinking skill is not maximal too.One of learning model that can improve students’ critical thinking skills is problem based learning.This study aims to determine the effect of problem based learning to students critical thinking skills on the excretory system.Samples of this study were XI IPA 1 as an experimental class and XI IPA 2 as the control class.This is a quasi-experimental research with posttest only control design.Variable that measured are students critical thinking skills obtained from the posttest scores than analyzed with biserial correlation and t-test.Students’ activity,students and teacher responses were analyzed by descriptive qualitative percentage.Based on the result,critical thinking skills average scores of experimental class was 76,93,while the control class was 65,67.The result of t-test showed that there is a significant influence between biology learning model of problem based learning to the students’ critical thinking skill at SMAN 1 Singorojo.Biserial correlation test showed that biology learning model of problem based learning have a strong relationship to the students’ critical thinking skills.Students’ activity analyzed showed that experimental class is higher than control class.The conclusion of this research is biology learning model of problem based learning have a effect there is increase students’ critical thinking skills.
关键词：Problem Based Learning;critical thinking skill;excretory system
