The purpose of this study is to find out the effect of Jigsaw I technique on students' academic success and attitude towards the course in teaching Turkish grammar. For that purpose, three grammar topics (spelling and punctuation marks rules) were determined and an experimental study conforming to "control group preliminary-testing final testing model" was conducted at a middle school located in Kars Turkey. As data collection tools "Success Test to measure effectiveness of Jigsaw I Technique in Grammar Teaching" (AST) and "Turkish Course Attitude Scale" (TCAS) were used. At the end of the study, it was discovered that there was no difference between the success scores of the students in experimental and control groups and their attitudes towards the course, in other words, the academic success of both group where Jigsaw I technique was applied and the group where conventional teacher centered teaching was applied after the experiment and their attitudes towards Turkish course were similar.