The top-ranked U.S. public schools in the 2021 Best High Schools rankings are those whose students earned outstanding scores in math and reading state assessments, took and earned a qualifying score in an array of college-level exams, and graduated in high proportions. Under U.S. News’ 2021 rankings methodology, nearly 18,000 public high schools were ranked using a comprehensive formula. The six ranking factors and their weights are explained in the rankings methodology.

The state rankings are calculated based on the proportion of each state’s schools in the top 25% of the 2021 Best High Schools rankings. That level of achievement is the most valid indicator of the relative performance of a state’s high schools compared with other states. This is because if a state has a relatively high percentage of its high schools in the top 25%, it demonstrates that those high schools have performed at the highest levels compared with other U.S. schools.