In this research, the effect of teaching with cooperative learning method and conventional learning methods on the academic success and attitudes of elementary school 8th grade students in Science and Technology lesson is analyzed comparatively. A testing and a control group that is randomly chosen from Sakarya city, Hendek district, An Elementary School 8th grade classes is formed for the research. “Substance and Energy for Living Things” unit is considered in both groups. The lessons in the testing group are treated with Ask Together, Learn Together technique of Cooperative Learning Method. In the research, achievement test and morale survey is applied to the testing and control group as pre-test and post-test. In order to profoundly consider these findings, pre and postinterviews are made with 6 students from the testing group. Unstructured observation technique is applied to the testing group in the course of the whole study. It is seen that cooperative learning method is more effective than conventional learning methods on attitudes to Science and Technology lessons. Although the final test scores of the experiment group students were higher than the final test scores of the control group students, the difference was not significant statistically. According to these findings, recommendations were suggested about the effect of cooperative learning method on improving the students’ achievement regarding science subjects.