That means D.C. officials need to start planning now, says a new study by D.C. Action for Children. The non-profit advocacy group studied OSSE and census data in collaboration with the Annie E. Casey Foundation to develop a compelling set of ward-level demographic snapshots.

D.C. State Superintendent of Education Hosanna Mahaley said that auditors verified 31,562 students in the independently operated charter schools as of fall 2011, up from 29,356 in fall 2010.

The 128 classrooms, spread across 54 public and public charter schools, represent less than three percent of classrooms citywide in which tests were administered last April. They were identified in a study last July by CTB/McGraw-Hill, publisher of the DC CAS, as having “inordinate numbers” of wrong-to-right erasures on answer sheets. The study, which wasn’t made public by OSSE until late December, said the data “may indicate inappropriate intervention on students’ answer documents by an educator.”

DCPS maintains a system of neighborhood schools with seats guaranteed to anyone within prescribed boundaries. The PCSB oversees schools open to all comers citywide. Decisions about openings, closings, program offerings and facilities have, more often than not, been made in isolation.