<![CDATA[The aim of this research was to find out the effect of PBL in students' writting communication skill and students' learning achievement. The design of this research was pretest and posttest non equivalent group. The samples of this research were students in the class VIIB and VIIC selected by purposive sampling. The quantitative data were obtained from the pretest posttest scores and the N-gain score that were analyzed by using t-test and the qualitative data were students' writting communication skill that analyzed descriptively. The result showed that the students' writing communication skill in the experiment class was good (78,64) criteria. The mean of N-gain of students' score in the experiment class was higher that was 74,55 than control class that was 48,45. Therefore, it can be concluded that PBL model improve the students' writting communication skill and students' learning achievement significantly.Tujuan penelitian ini untuk mengetahui pengaruh model PBL terhadap keterampilan berkomunikasi tertulis dan hasil belajar siswa. Desain penelitian adalah pretest-postest kelompok tak ekuivalen. Sampel penelitian ini adalah siswa kelas VIIB dan VIIC, yang dipilih secara purposive sampling. Data kuantitatif diperoleh dari nilai pretest, postest, dan N-gain yang dianalisis menggunakan uji t dan data kualitatif berupa keterampilan berkomunikasi tertulis siswa diperoleh dari analisis secara deskriptif. Hasil penelitian menunjukkan keterampilan berkomunukasi tertulis kelas eksperimen berkriteria Baik (78,64). Rata-rata N-gain hasil belajar siswa pada kelas ekperimen lebih tinggi sebesar 74,55 dibandingkan kelas kontrol sebesar 48,45. Dengan demikian, dapat disimpulkan bahwa model PBL meningkatkan keterampilan berkomunikasi tertulis dan hasil belajar siswa secara signifikan.Kata kunci: hasil belajar, keterampilan berkomunikasi tertulis, Problem Based Learning]]>
