Interns play a key role in medical student education, often observing behaviors that others do not. Their role in assessment, however, is less clear. Despite accreditation standards pertaining to residents' assessment skills, they receive little guidance or formal training in it. In order to better prepare residents for their role in medical student assessment, we need to understand their current experience. We aimed to describe the first-year resident experience assessing students' performance and providing input to faculty for student clinical performance assessments and grades in the inpatient setting. Pediatric interns at Children's National Hospital (CN) from February 2018 to February 2019 were invited to participate in semistructured interviews about their experience assessing students. Constant comparative methodology was used to develop themes. Ten interviews were conducted, at which point thematic saturation was reached. We identified 4 major themes: 1) Interns feel as though they assess students in meaningful, unique ways. 2) Interns encounter multiple barriers and facilitators to assessing students. 3) Interns voice varying levels of comfort and motivation assessing different areas of student work. 4) Interns see their role in assessment limited to formative rather than summative assessment. These findings depict the intern experience with assessment of medical students at a large pediatric residency program and can help inform ways to develop and utilize the assessment skills of interns.