Chicago Public Schools chief Arne Duncan will recommend today that some two dozen schools be closed or consolidated.

Schools will be shut down for two main reasons—underenrollment or poor performance. At schools closed due to low test scores, all staff will be let go. New staff will be put in place by September, and at least some of the schools will be handed over to outside management firms to run.

Board president Rufus Williams says he understands school closures cause angst, but believes students and parents will thank the districct in the end.

WILLIAMS: I am truly troubled by the number of schools we have performing at the lower levels. We have to do better for each and every one of those children, and we have to do it with a sense of urgency.

The board must sign off on all recommended closures and consolidations. But since CPS began the practice in 2004, the board has never rejected a recommendation. It’s closed 61 schools in that time.