A new charter school will open in the fall of 2008 in Pittsburgh's East End. The PPS board last approved a charter for the Environmental Charter School at Frick Park -- an Imagine School. Community organizers brought in Arlington, Va.-based Imagine Schools to run the school, which will open in September, 2008, with about 250 students in kindergarten through third grade. It will operate in the former Regent Square Elementary building, which the charter's organizers purchased from the school district for $3 million in 2006.