The background of this research is due to problems in learning computer systems at school. The purpose is to find out the improvement of students' cognitive aspects by applying a cooperative script method assisted by interactive multimedia on the subject of the computer system. The method used is an experimental method with a quasi-experimental form. The research design used is a nonequivalent control group design. Before conducting the research, the multimedia was validated first by the expert of material and the expert of multimedia. Based on the data processing, the result are 1) the improvement of the cognitive aspect in a control class has a gain index 0.37, while in the experiment class is 0.78. 2) The multimedia has a good response from the students and reached the percentage of 78.51%.