The Dayton (Ohio) district is moving students from the Van Cleve at McGuffey School to the former Allen Elementary School building to protect against air vapors from a nearby chemical spill. The move will mean classes will start Aug. 13 for Van Cleve students, a week later than other schools. Since October, the U.S. Environmental Protection Agency has been testing near the school and monitoring the movement of a plume of trichloroethylene, a product used for dry cleaning and metal cleaning. July testing showed elevated levels of the vapors in the school. The district was advised to install a venting system to expel the vapors from the school, but school officials decided to send students away from the building.