<![CDATA[ABSTRACT ? The purpose of this research is to improve students? science process skills in class X5 SMA Negeri 6 Surakarta in academic year 2011/2012 with implementation of Group Investigation cooperative learning model. This research was a classroom action research and performed in 2 cycles. Every cycle consists of 4 steps, namely planning, action, observation, and reflection. The data were collected by observation, questionnaire, and interview. The data were validated by triangulation method. The collected data were supported by the result of students? science process skills test in the last cycle. The analyzed technique used descriptive analysis. The result of this research showed that according observation sheet the average percentage of science process skills aspect in the cycle I was 52,57% and had been improved up to 80,36% in cycle II. The average percentage of science process skills aspect based on quetionnaire in cycle I was 84,22% and 86,56% in cycle II. According to the students interview,could be concluded that the students were able to do science process skill in learning process. The data of science process skill test in cycle I, the student that got test result ? 70 was 25% and in cycle II was 67,86%. The average test result of the class in cycle I was 60,27 had been improved up to 67,14 in cycle II. The conclusion of this research was the implementation of Group Investigation (GI) cooperative learning model could improve students science process skills in class X5 SMA Negeri 6 Surakarta in academic year 2011/2012. Keywords: Group Investigation (GI), Science Process Skills]]>
