The purpose of the study was to examine general music teachers' practices of cooperative learning in two elementary music classrooms. Using the intrinsic case study method, I examined elementary general music teachers' perspectives on cooperative learning, the utilization of cooperative learning in their general music classrooms, and the challenges the music educators faced in creating and implementing cooperative learning. I selected one general music classroom in two elementary schools in Boston, Massachusetts--totaling two general music teachers from different schools. I conducted eight class observations and three interviews for each participant during the fall 2016 semester. From separate and cross-case analyses, I found the following: (1) the two teachers' instructions were linked to the characteristics of cooperative learning, (2) they believed that cooperative learning provided opportunities to improve students' academic development in music and promote positive interpersonal relationships, and (3) both teachers used their own strategies for cooperative learning in order to maximize students' learning. These findings provided evidence that cooperative learning engaged students in the process of learning music and, in addition, fostered positive interpersonal relationships. Moreover, this study suggested that music educators might undertake an effort to thoroughly understand students' cognitive development when they wish utilize cooperative learning. Although this study was subject to a number of limitations due to its scope, the findings may contribute to the body of research on cooperative learning in elementary music education. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]