Preparing general education preservice teachers (PSTs) to work with English language learners (ELLs) effectively is of critical importance given the continually increasing number of these students in mainstream classrooms in the United States. In this qualitative study, we investigated the impact of a semester-long course on teaching ELLs on senior-level PSTs' perceptions of preparedness to teach ELLs in mainstream classroom settings. We purposefully selected 18 senior-level general education PSTs attending a mid-sized urban public university in the southwest United States. We collected data through demographic data sheets and pre- and post- course written reflections. We analyzed the qualitative data via thematic analysis. Results indicated that PSTs' confidence and perceptions of preparedness to teach ELLs in mainstream classrooms increased after completing a semester of coursework focused on teaching ELLs.