Lyon City School District (CSD), an urban center located in up-state New York serves over 37,000 students spending $9,900 annually with 91% of its students receiving free or reduced lunches and 74% of its population classified as racial minorities. Lyon CSD also possesses the second highest number of SURR schools outside of New York City under No Child Left Behind Act of 2001 (NCLB) regulations. Bearing this in mind, as well as the increasingly critical eye cast on the actions of high school principals in an era of accountability reforms, this study posed the following three questions: (1) What are high school principals' perceptions of high-stakes, standardized assessments; (2) What are their self-described daily practices in response to these assessments; and (3) To what extent are their self-described practices consistent with their perceptions? Six principals from Lyon were selected to represent the three main categories of NCLB school classification, AYP, SRAP, and SURR, and participated in multi-part, three-session interviews. The first two interviews focused on gaining an understanding of these principals' perceptions of standardized assessments with the final interview focusing on their daily practices in response to these assessments. Principals reported that: (1) instructional time is perceived as lost as a result of the assessments; (2) classroom pedagogy is often becoming standardized and reduced to a skill and drill process; (3) external social factors are a significant negative influence on students' academic performance; and (4) intensification of cognitive and emotional demands and stress on students and teachers resulted in less attention to students' social and emotional well-being. Principals' responses also suggested that: improved test scores serve as the principals' de facto school vision; test data, while delayed in being returned, are not often used for diagnostic purposes; and curricula are being narrowed with the inclusion of tested subjects such as reading in other non-tested subjects in ways that suggest displacement of, rather than a claimed integration with, other subject matter.