ABSTRAK
Penelitian ini bertujuan untuk meningkatkan kualitas pembelajaran yang meliputi performance guru, kemanfaatan fasilitas pembelajaran di kelas, iklim kelas, sikap ilmiah siswa, dan motivasi belajar siswa menggunakan model pembelajaran Group Investigation pada materi ekosistem di kelas X.8 SMA Negeri 5 Surakarta Tahun Pelajaran 2012/2013.
Penelitian ini merupakan penelitian tindakan kelas yang dilaksanakan dalam tiga siklus.Setiap siklus terdiri atas 4 tahapan yaitu perencanaan, tindakan, observasi, dan refleksi.Pengumpulan data penelitian menggunakan angket, observasi, dan wawancara.Teknik validasi data menggunakan teknik triangulasi metode dan triangulasi observer. Teknik analisis data menggunakan teknik deskriptif..
Hasil dari penelitian menunjukan bahwa berdasarkan triangulasi rata-rata aspek:  performance guru prasiklus 58,54%, siklus I 89,58%, dan siklus II 96,87%; iklim kelas pra siklus 68,72%, siklus I 74,37%, dan siklus II 85,27%; Sikap Ilmiah siswa pra siklus 59,13%, siklus I 69,86%, dan siklus II 83,76%; Motivasi Belajar Siswa pra siklus 69,15%, siklus I 79,02%, dan siklus II 80,42%.Fasilitas pembelajaran juga sudah digunakan secara optimal. Hasil menunjukan bahwa rata-rata capaian  persentase aspek kualitas pembelajaran biologi untuk prasiklus 63,85%,  siklus I 78,27%, dan siklus II 86,58%. Adapun peningkatan aspek kualitas pembelajaran biologi dari hasil prasiklus sampai siklus III sebesar 33,34%.Siklus dihentikan pada siklus II karena target penelitian sudah tercapai. Kesimpulan dari penelitian ini adalah bahwa penerapan model pembelajaran Group Investigation dapat meningkatkan kualitas pembelajaran biologi yang meliputi aspek performance guru, iklim kelas, sikap ilmiah siswa, motivasi belajar, dan kemanfaatan fasilitas pembelajaran pada siswa kelas X. 8 SMA Negeri 5 Surakarta tahun pelajaran  2012/2013.
Kata Kunci : model pembelajaran Group Investigation, Kualitas pembelajaran Biologi
ABSTRACT
The aims of the research is to increasethe quality of biology learning,considered by teacher’s performance, utility of facilities in the classroom, classroom climate, student’s scientific attitude, and student motivation of achievement using group investigation learning model on ecosystem subject in class X.8 SMA Negeri 5 Surakarta in academic year 2012/2013.
This research was a classroom action research which performed  in three cycles. Each  cycle  consist  of  4  phases, which is planning, action, observation, and reflection. The data  was  collected  by questionnaire, observation, and interview. The data wasvalidatedbytriangulation  methods and triangulation observers. The obtained data were analyzed using qualitativedescriptive technique.
The results of this research showed that according to the triangulation of method and triangulation of observer, the average percentage for  teacher’s performance in pre cyclewas58,54%, cycle Iwas 89,58%, and cycle II was 96,87%; the average of classroom climate pre cycle was 68,72%, cycle I was (74,37%), and cycle II was (85,27%); the average of student’s scientific attitude  pre cycle was 59,13%, cycle I was69,86%)\, and cycle II was 83,76%; and the average ofstudent motivation of achievement in pre cycle was69,15%, cycle I was 79,02% and cycle II was 80,42%. Theutility of learning facilities in the classroom have been optimally. The  results  showed  that  the  average  percentageof the quality of biology learning’s aspect from  pre cycle (63,85%),  cycle I (78,27%), and cycle II (86,58%) was increase by 33,34%.Cycles stopped in cycle II because the research’s target was achieved. The conclusion of this research describes that the implementation of group investigation learning model can increasethe quality of biology learning considered by teacher’s performance, utility of facilities in the classroom,  classroom climate, student’s scientific attitude, and student motivation of achievement in class X.8 at SMA Negeri 5Surakarta in academic year 2012/2013.
Keywords: Group Investigation learning model, , Quality of biology learning, ecosystem