View Comments The top-ranked public high schools in the country do two things really well: They graduate their students and they prepare them for college. U.S. News & World Report ranked nearly 18,000 public high schools (a mix of charter, magnet and traditional schools) using state education data from the 2018-2019 school year to come up with its latest ranking of schools. One Delaware school, Charter School of Wilmington, made the national top 100 at No. 74. Here's how the rankings were calculated: College readiness, based on the proportions of 12th grade students who took and earned a qualifying score on AP and/or IB exams.