This study was conducted to determine the themes present in the context of high schools, to determine any significant differences in themes for high and low performing high schools, and to determine if significant differences were present for the same sample of high schools based on school size. An analysis of the content of mission statements identified 31 dominant themes: Students, Providing, All, Community, Learning, Academics, Developing, Responsible, Education, Environment, Preparing, Productive, Success, Lifelong Learning, Individual, Citizen, Excellence, Skills, Society, Committed, Promotes, Achievement, Diversity, Knowledge, Nature, Challenge, Future, Partnership, Quality, Potential, and Safe. Significant differences were found between the group of high and low performing high schools for the themes of Academics, Excellence, Challenge, Learning, Nurture, and Lifelong Learning (p less than or equal to 0.05). Analysis of mission statements grouped by size yielded a significant difference for the theme of Knowledge for large size high schools as compared to small and medium size high schools.