PHILADELPHIA (CBS) — The City Controller says some Philadelphia schools risk losing federal grants because they’re understaffed.

In an audit of the School District of Philadelphia, City Controller Alan Butkovitz says 17 of 23 schools examined last year didn’t have enough staff for the number of students enrolled. He says that puts the district at risk of losing Title I grants, provided for low-income students.

The audit shows the district was a total of 48 staffers short, with the worst ratios at Frankford, Ben Franklin and Bartram High Schools and Ethan Allen and Huey Elementary Schools.

The district is taking steps to address the issue: Spokesman Lee Whack says a multimedia ad campaign to recruit teachers has generated 800 applications to fill teaching positions next year.