Inclusion teachers at the elementary level face challenges in differentiating instruction for all students. Despite inclusion teachers' willingness to use differentiated instruction (DI), many teachers struggle implementing DI because of teachers' understanding of DI, insufficient time for planning, and insufficient training and resources. The purpose of this qualitative case study was to explore the experiences of 8 elementary inclusion teachers who implemented DI in their classrooms in a southeastern school in Georgia. Vygotsky's theory of constructivism served as the theoretical framework for this study. Key research questions focused on teachers' perceptions regarding their implementation and use of DI in inclusion classrooms. Data were collected through individual interviews, classroom observations, and lesson plans and were analyzed using open, axial, and selective coding to sort and form themes. Key findings revealed that although inclusion teachers readily implemented DI, they varied in their understanding and application of DI strategies and activities. Inclusion teachers limited their selection and use of DI strategies to flexible grouping, tiered assignments, and technology. Teachers indicated that DI instruction resulted in improved classroom management and student learning. Although inclusion teachers applied DI strategies and activities, they need further DI training and planning time to improve lessons geared to reach individual learning needs. It is recommended that teachers select alternative research-based DI strategies to improve instruction in inclusion settings. These actions could contribute to positive social change by increasing teachers' knowledge of and the benefits of DI; thus, maximizing students' academic potential in high school and opening educational opportunities in higher 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.]