<![CDATA[AbstractThe Effectiveness of Group Investigation Model on Student Learning Outcomes of Class III SDN Mranggen 2. This research is aimed is know the effectiveness of Group Investigation model in science lesson of student in class III. This type of research is quantitative research with Quasi Experimental Design research design and the type taken is Non Equivalent Control Group Design. The sampels which taken were 28 students in class IIIB as experimental class and 28 student in class IIIC as control class by using Non Probability Sampling technique with saturated sampling. The result of the research shows that the average value of posttest of experimental class is higher, that is in class IIIB of 78,57 while, the average value of posttest control class that is in class IIIC equal to 69,10. Based on data analysis on the calculation tets-t obtained tcount 2,304 and ttabel=1,673. Because tcount> ttabel, then H0 rejected and Ha accepted, then concluded Group Investigation model effective on science learning outcomes of third grade students of SD Negeri Mranggen 2.Keywords: Model Group Investigation, Learning Outcomes AbstrakKeefektifan Model Group Investigation Terhadap Hasil Belajar IPA Siswa Kelas III SDN Mranggen 2. Penelitian ini bertujuan untuk mengetahui efektifitas dari model Group Investigation pada mata pelajaran IPA siswa kelas III. Jenis Penelitian ini adalah penelitian kuantitatif dengan desain penelitian Quasi Eksperimental Design dan jenis yang diambil adalah Non-Equivalent Control Group Design. Sampel yang diambil adalah 28 siswa kelas IIIB sebagai kelas eksperimen dan 28 siswa kelas IIIC sebagai kelas kontrol dengan menggunakan teknik Non Probability Sampling dengan sampling jenuh. Hasil Penelitian diperoleh rata-rata nilai posttest kelas eksperimen lebih tinggi yaitu pada kelas IIIB sebesar 78,57 sedangkan pada rata-rata nilai posttest kelas kontrol yaitu pada kelas IIIC sebesar 69,10. Berdasarkan analisis data pada perhitungan uji t diperoleh nilai thitung =2,304 dan ttabel =1,673. Karena thitung > ttabel, maka H0 ditolak dan Ha diterima, maka disimpulkan model Group Investigation efektif terhadap hasil belajar IPA siswa kelas III SD Negeri Mranggen 2.Kata Kunci : Model Group Investigation, Hasil Belajar]]>
