Tujuan penelitian ini untuk mengetahui Perbedaan Pemahaman Konsep Biologi Siswa dengan Model Pembelajaran Problem Based Learning dan Problem Posing di Kelas XI SMA Muhammadiyah Tarakan. Penelitian ini dilakukan selama bulan April 2015 di SMA Muhammadiyah Tarakan. Penelitian ini menggunakan eksperimen semu (quasi eksperiment) dengan populasi seluruh siswa kelas XI SMA Muhammadiyah Tarakan Tahun Ajaran 2014/2015, dan sampel yaitu kelas XI IPA 1 sebagai kelas eksperimen 1 dan kelas XI IPA 2 sebagai kelas eksperimen 2. Teknik pengambilan sampel menggunakan Purposive Sampling dan teknik pengumpulan data menggunakan dokumentasi, observasi dan tes uraian. Data dianalisis menggunakan software SPSS 16.0 for Windows. Berdasarkan hasil analisis data dapat disimpulkan bahwa terdapat perbedaan penerapan model pembelajaran Problem Based Learning dengan Problem Posing terhadap pemahaman konsep siswa kelas XI SMA Muhammadiyah Tarakan, karena nilai thitung yang diperoleh sebesar 2,297 lebih besar dari ttabel 1,673
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The study aimed of the research is to know the differences between Problem Based Learning and Problem Posing of students’ biology concept at the XI grade students of SMA Muhammadyah Tarakan. The research was taken since April 2015 at SMA Muhammadyah Tarakan. The research design is quasi experimental. The population of the study is the grade XI students of SMA Muhammadyah Tarakan Academic Year 2014/2015,the samples of the study are grade XI IPA I as the experiment 1 and grade XI IPA II as the experiment 2. The technique sampling is purposive sampling technique. To collect the data, the researcher uses documentation, observation, and test. To analyze the data, the researcher uses SPSS Version 16.0 for windows. Based on the data analysis, it can conclude that any differences between Problem Based Learning and Problem Posing of students’ biology concept at grade XI students’ of SMA Muhammadyah Tarakan. The result is higher than ttable. There are 2,297 higher than t-table 1,673.