Confronting the ever-increasing demands of high-stake testing, districts have had to evaluate the efficacy of a school’s educational leadership in order to increase student achievement. Schools that have high ratios of economically disadvantaged and special needs students have felt the desperation of insurmountable accountability goals. The focus of this study was to determine if there were a relationship between a principal’s leadership ability and standardized test scores in Title I high schools. The specific research questions were: (1) Is there a relationship between a principal’s instructional leadership practices and Gateway Exam scores in lower-performing and higher-performing Title I high schools? (2) Is there a difference in teachers’ perceptions of the learning environment in lower performing and higher-performing Title I high schools? (3) Is there a difference between teachers’ perceptions of the principal’s expectations in lower-performing and higher-performing Title I high schools? Data utilized in this study were collected from a public website and surveys completed by teachers in 32 Title I high schools. There were 750 surveys collected from Title I high school teachers. The surveys were used to measure the teachers’ perceptions about their principals’ leadership practices, quality of the learning environment, and the school’s instructional expectations. The data used to measure student achievement were collected from standardized test scores posted on a public website. Three consecutive years of test scores were collected for first-time-test-takers in the same 32 Title I high schools. Each school was assigned a consolidated mean test score based on the three year average scores for the Math and Language Arts Gateway exams. The analysis of the data was quantitative and utilized a multiple regression model for research question one and a MANOVA to answer research questions two and three. The relationship between the principal’s instructional leadership and learning environment were not statistically significant. However, the descriptive statistics indicated that the perceived principal’s instructional expectations were statistically significant in higher-performing Title I high schools.