Since 1998, The Post’s Jay Mathews has ranked Washington-area public high schools using the Challenge Index, his measure of how effectively a school prepares its students for college. In 2011, the Post expanded its research to high schools across the United States.
The formula is simple: Divide the number of Advanced Placement, International Baccalaureate or other college-level tests a school gave in 2010 by the number of graduating seniors. While not a measure of the overall quality of the school, the rating can reveal the level of a high school’s commitment to preparing average students for college.
West Potomac High School in Fairfax County and Oakland Mills High School in Howard County are as close as schools come to being twins. Both are in affluent counties and serve ethnically and economically diverse populations. Forty-seven percent of West Potomac students and 52 percent of Oakland Mills students are black or Hispanic. Thirty-eight percent at West Potomac and 31 percent at Oakland Mills are from low-income families.
But when I indulge in my obsessive comparison of schools by their college-level course programs, significant differences emerge. Oakland Mills often bars students from taking Advanced Placement classes if they don’t have B’s in previous courses. West Potomac lets in everyone who signs up and pays the test fees. The AP test participation rate at West Potomac is three times what it is at Oakland Mills, but the passing rate on tests at the Fairfax school is lower: 61 percent, compared with 78 percent at Oakland Mills.