My old high school, Princess Anne, was apparently the 143th best public high school in the nation according to a 2005 Newsweek article. Crazy. They used a simple ratio of adding up the number of AP and IB tests the student body took divided by the number of graduating seniors. The usefulness of this metric is discussed in the collection of articles.
Princess Anne’s ratio is much much much higher that what is was when I was there… like, say, 20x to pull an unsupported stat out of the ether. They did not have an IB program there when I was around, and many more people must be taking AP tests and/or taking mroe of them.
They did not count magnet public high schools that had admission tests and whatnot like Stuyvesant, Bronx Science, IMSA, and the like as they would completely crush the competition. The rationale was that those schools had a selectively skewed population making comparisons silly (as they are obviously “better” academicly than a normal public school).