Does South Carolina have the worst schools in the U.S.?

If one believes Neighborhood Scout and its list of the 100 Worst Public Schools in America, South Carolina has the worst schools in the country, claiming 11 of the 25 "top" spots on the list. Chicago and Milwaukee also seem to be hotbeds for failure, claiming four and three of the "top 25" positions, respectively. But its a school from East St. Louis (Tomorrows Builders Charter School) that earned the ranking of worst in America, with zero 11th grade students proficient in math and just three percent proficient in reading.