Due to numerous mandates in the educational field, it is imperative to schools that teachers incorporate effective instructional methods to reach the diverse student population within a classroom. One way some educators have chosen to meet these challenges is by using the co-teaching model. In this setting, two or more teachers work in a collaborative environment to deliver instruction to a heterogeneous group of students in a shared physical space. This research was completed to determine the perceptions of students and teachers on the overall effectiveness of this strategy and its effect on discipline referral rates and achievement. The study presented the history and overview of the strategy and highlighted the practice of this model in schools through literature. Analyzing 233 student surveys and completing 30 interviews with participating students and teachers, perceptions of the classroom were established, from which many benefits were determined. Perceptions of the effectiveness of the co-teaching strategy were overwhelmingly positive. From student surveys and interviews, as well as the teacher interview, most co-taught participants supported this practice. Using a t-test of proportions on discipline referral rates and a t-test of means on common post-tests, the co-taught classroom and a control classroom with similar demographics were compared. Although discipline rates were lower and post-test scores were higher in the co-taught class, these differences were not statistically significant. Some interesting aspects were raised from the quantitative and qualitative analysis, and further study is needed. This instructional strategy should be studied in greater detail to find out if particular grade levels or content areas could benefit from this practice. [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.]