AbstrakTujuan Penelitian ini adalah untuk meningkatkan aktivitas belajar siswa dengan menerapkan Pendekatan Saintifik dan model pembelajaran kooperatif tipe Think Talk Write (TTW). Subjek penelitian ini berjumlah 30 yaitu siswa kelas VII B SMP Negeri 1 Bengkulu Tengah Semester genap tahun ajaran 2016/2017. Jenis penelitian adalah Penelitian Tindakan Kelas (PTK) yang dilaksanakan dalam tiga siklus dengan alur penelitian yaitu perencanaan, tindakan, pengamatan, dan refleksi. Instrumen penelitian ini yaitu lembar observasi aktivitas belajar siswa. Hasil penelitian menunjukkan bahwa penerapan Pendekatan Saintifik dan model pembelajaran kooperatif tipe TTW dapat meningkatkan aktivitas belajar siswa. Peningkatan aktivitas belajar siswa dapat dilihat dari rata-rata skor pada lembar observasi aktivitas belajar siswa dari siklus I hingga siklus III secara berturut-turut: 21,17 (kriteria cukup aktif); 26,33 (kriteria aktif); 31,84 (kriteria aktif).Kata Kunci: Pendekatan Saintifik, Model Think Talk Write dan Aktivitas Belajar Siswa AbstractThe purpose of this study was to improve student learning activities by applying the Scientific Approach and cooperative learning model type Think Talk Write (TTW). The subjects of this study is 30 students of class VII B SMP Negeri 1 Bengkulu Tengah 2016/2017 academic year. The type of research is Classroom Action Research (PTK) which is implemented in three cycles with the three steps:planning, action, observation, and reflection. Instrument used in this research was observation sheet of student learning activity. The results showed that the application of the Scientific Approach and cooperative learning model type TTW could improve student learning activities. Increased student learning activity could be seen from the average score on the observation sheet of student learning activities from cycle I to cycle III with criteria respectively: 21.17 (active enough); 26.33 (active); 31.84 (active).Keywords: Scientific Approach, Think Talk Write Model and Student Learning Activities