The school board and the city council are locked in a dispute that could delay next month's opening of city schools. The school board says classes won't start on Aug. 8 unless the city pays $55 million it owes in school funding. The mayor says he doesn't have the money. And besides, the city doesn't usually have to pay until September. The board and council rarely get along, so it's not clear if they will come up with a compromise in time for classes to start.