The objectives of this study were: To determine the improvement of discussion skills through the cooperative learning model type Investigation Group in the subjects of PPKn for Grade VI students of SD Negeri 34 Ampenan. Based on the results of the achievement of the research indicators as follows: 1) The use of the Group Investigation cooperative learning model on the PPKn study material is proven to improve the discussion skills of the VI grade students of SD Negeri 34 Ampenann. This can be seen from observing teacher activity and observing student activity in cycle I and cycle II. Thus the increase in teacher activity in learning has increased 19%, namely from 71.88% from cycle I to 90.63% in cycle II. Student activity also increased by 15%, namely 72.50% in cycle I and increased to 87.50% in cycle II; 2) Students' mastery of learning material shows an increase. This is evidenced by the mean value of daily test results (the average daily test results without the use of the Group Investigation Group type cooperative model 79.46 to 83.10 and to 85.74 after the use of the Group Investigation type cooperative model).