Cooperative learning may have beneficial impact on classroom teaching. The study aimed to identify the effect of cooperative learning in writing ability of the 7th class students in the subject of English. The population of the study consisted of 68 students enrolled at elementary level (7th grade) in Government Girls High School Burj Attari, Sheikhupura. There were two sections of 7th grade in the school and 34 students in each section. The study was Quasi Experimental with a Non-equivalent control group, pre-test and post-test design. One section was randomly selected as experimental group (X1) and the other was assigned to control group (X2) on the basis their previous class results. The results describe there is a significant difference between post-test scores of control and experimental group. Findings of the current study reveal that cooperative learning method is more effective than the grammar translation method among students. It is recommended that teachers might apply cooperative learning techniques to improve students' writing skill in the classroom