Secondary school administrators play a vital role as instructional leaders, but little is known about their knowledge of science practices and perceptions of strategies for supporting reform‐oriented science instruction. This multiphase, mixed‐methods Q‐Methodology study explored administrators' perceptions of instructional leadership and, in particular, high‐quality science instruction. After a concourse of 40 items was developed through a review of literature and an expert panel, n = 22 administrators from one urban school district completed a Q‐sort and a post‐sort questionnaire in which they commented on a lesson excerpt. Principal components analysis with varimax rotation was used to assimilate the participants into three factors or groups explaining 40% of the variance. A subsample (n = 14) of administrators then participated in focus groups to engage in collective sensemaking. Although administrators consistently valued positive teacher‐student relationships and had high expectations for all students over other managerial duties, perceptions of how to support teachers and their ability to detect evidence‐based science pedagogy (NGSS), differed. Administrators with a science background or more experience as an administrator were more familiar with some of the evidence‐based instructional strategies for science included in the sample lesson. Administrators without such a background tended to emphasize general pedagogical techniques. We discuss implications for the development of school leaders with varying disciplinary backgrounds as one component of building districts' capacity for high‐quality science instruction.