This dissertation explored the unique experiences of general education teachers teaching in an inclusive classroom (which will also be referred to as a "mainstream classroom") with a combination of students with and without autism (which will also be referred to as "autism spectrum disorder" and "ASD"). This was a qualitative research study that applied the "Interpretative Phenomenological Analysis" (IPA) research method, as presented by Smith, Flowers, and Larkin (2009). The participants in this study were seven general education teachers, each of whom taught kindergarten or fourth grade. Purposive sampling was used to gain a better understanding of the teachers' experiences across the elementary school careers of students with autism. Four teachers taught in Massachusetts, two in New Jersey, and one in New York City. Out of the seven participants, three were kindergarten teachers and the remaining four were fourth-grade teachers. Through semi-structured interviews, participants' experiences were shared. The data analysis involved generating emergent and superordinate themes of teacher perceptions to aid in the understanding of the teachers' experiences. This study explored whether these experiences differed across grade levels and geographic locations, and how they compared across the full data set. Finally, the findings were discussed in the context of previous literature, what the limitations were to this study, what future directions there were for research on this topic, and my personal reflection. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]