The purpose of this action research was to determine if Kagan Cooperative Learning Structures produced greater achievement in music education than those who did not have the opportunity to engage in Kagan structures. The participants included 114 fourth grade students attending a public school in southern Minnesota. The scores of pre and post-tests determined student growth and achievement for both the control and treatment groups. The specific music skill assessed was rhythm. Results indicated that there was a statistically significant difference on rhythm when assessed by a paper and pencil exam when Kagan Structures were used. Analysis of a performance assessment determined there was no statistical evidence to support the conclusion that the use of Kagan Structures was effective in rhythmic performance.