Evaluating comments from pre-service STEM teachers before and after their first teaching experience, this study examines changes in pre-service STEM teachers' viewpoints regarding the most challenging aspect of teaching and the most important traits of a teacher. Pre-service STEM teachers were asked the same survey questions on the first and last days of their initial introduction to STEM education course. Through this course, students partook in their first opportunity to plan and teach a lesson. Findings suggest students initially reviewed teaching from an extrinsically observable vantage point before moving to a more intrinsic reflection point after their first teaching experience.