Hasil belajar mata pelajaran Ilmu Pengetahuan Alam kelas VII di Sekolah Menengah Pertama Surabaya masih tergolong rendah. Hal ini dibuktikan dengan nilai ulangan tengah semester terdapat  45% peserta didik kelas VIII di SMP Taman Pelajar Surabaya yang mencapai nilai KKM dan 40% peserta didik di Mts. Nyai H. Asfiyah Surabaya yang mencapai KKM. Oleh karena itu untuk dapat meningkatkan hasil belajar peserta didik perlu dipilih model pembelajaran yang sesuai dengan karakteristik materi, karakteristik peserta didik dan tujuan pembelajaran. Salah satu model pembelajaran yang sesuai yaiu Problem Based Learning. Tujuan dari penelitian ini adalah mengetahui pengaruh penerapan model pembelajaran Problem Based Learning  terhadap hasil belajar peserta didik pada materi pokok Massa Jenis mata pelajaran Ilmu Pengetahuan Alam kelas VII di Sekolah Menengah Pertama Surabaya. Penelitian ini menggunakan pendekatan kuantitatif dan data yang digunakan berupa angka dan analisis statistik. Metode penelitian yang digunakan yaitu metode Quasi Experimental Design dengan bentuk Non Equivalent Control Group Design, dimana peserta didik kelas VII di SMP Taman Pelajar sebagai kelompok eksperimen dan peserta didik kelas VII di Mts. Nyai H. Asfiyah sebagai kelompok kontrol. Teknik analisis data yang digunakan yaitu analisis observasi dan analisis data tes tulis. Hasil penelitian diketahui data hasil observasi guru dan observasi peserta didik tergolong kriteria baik sekali dalam menerapkan model pembelajaran Problem Based Learning. Nilai pretest dan posttest kelompok eksperimen mengalami peningkatan hasil belajar yang signifikan yaitu thitung  6,057 > ttabel 1,99045. Dengan demikian Ho ditolak dan Ha diterima, sehingga dapat disimpulkan bahwa terdapat pengaruh terhadap hasil belajar peserta didik kelas VII Sekolah Menengah Pertama Surabaya setelah menerapkan model pembelajaran Problem Based Learning pada mata pelajaran Ilmu Pengetahuan Alam materi pokok Massa Jenis. 

kata kunci : Problem Based Learning, IPA, hasil belajar.

The learning outcomes of Science VII class at Surabaya Junior High School is still relatively low. This is proved by the midterm scores about 45% of class VIII students in Taman Pelajar Junior High School have achieved a standard grade of graduation and 40% of students in Mts. Nyai H. Asfiyah Surabaya who reached the graduation standard. Therefore to be able to improve the learning outcomes of students it is necessary to choose a learning model that is suitable with the characteristics of the material, the characteristics of the students and the learning objectives. One of suitable learning model is Problem Based Learning. The purpose of this study is to determine the effect of the application of the Problem Based Learning model of learning outcomes of students on the subject matter of the Density of the seventh grade Science subjects in Surabaya Junior High School. This study uses a quantitative approach and the data used in the form of numbers and statistical analysis. The research method used is the Quasi Experimental Design method in the form of Non Equivalent Control Group Design, where students in class VII at Taman Pelajar Junior High School are as an experimental group and students in class VII in Mts. Nyai H. Asfiyah as a control group. Data analysis techniques used were observation analysis and written test data analysis. The final result of this research point out the data of teacher observations and student observations classified as excellent criteria in applying the Problem Based Learning model. The pretest and posttest scores of the experimental group experienced a significant increase in learning outcomes namely tcalculation 6.057> ttable 1.99045. Thus Ho is rejected and Ha is accepted, so it can be concluded that there is an influence on the learning outcomes of Grade VII students of Surabaya Junior High School after applying the Problem Based Learning model in the Sciences subject matter of the Specific Density.

Keyword : Problem Based Learning, Sciences, Learning Outcome