UPDATE, 6:15 p.m.

Continued poor performance by the outside firm hired to provide substitute teaching services for the Philadelphia School District "puts this partnership in jeopardy," Superintendent William R. Hite Jr. said Thursday night.

Speaking at the September School Reform Commission meeting, Hite said Source4Teachers was tapped by the SRC to handle sub services because it was "a partner with experience."

The Cherry Hill firm handles substitute staffing for more hundreds of districts locally and nationally, though Philadelphia is its largest contract to date.

Hite said he was "extremely disappointed" in the firm's performance to date. Its best fill rate to date is about 15 percent, up from 11 percent at the beginning of the year. It promised 75 percent on the first day of school, ramping up to 90 percent by January.

The superintendent said that the district is working closely with Source4Teachers, which will offer increased pay. The firm previously said it did not believe pay was a factor in its poor performance. Teachers are paid up to $110 per day by Source4Teachers; a retired sub could make over $200 when the district ran the substitute service.

Hite also said that Source4Teachers would explore using a subcontractor to fill jobs.

SRC chairwoman Marjorie Neff called Source4Teachers' performance "unacceptable" and said the commission takes full responsibility for selecting the vendor. Neff said that the firm's performance must improve "drastically."

She noted that the move to outsource substitute services was "not about cutting costs, it was about solving a problem."

EARLIER:

In advance of tonight's scheduled School Reform Commission meeting (5:30 p.m.; livetweeting recap below) PFT President Jerry Jordan has called on the SRC to cancel its contract with Source4Teachers, the firm paid $34 million to handle substitute-teaching services.

The SRC voted in June to pay the Cherry Hill-based firm $34 million over two years to staff city classrooms with teachers and other school staff. The district had previously handled substitute staffing itself, achieving only about a 65 percent fill rate on vacancies.

It promised Source4Teachers would do better. The firm must staff 90 percent of vacancies by January or face financial penalties.

Schools are facing hardships because of the company's inability to perform, Jordan said.

Kristen Graham live-tweeted from tonight's School Reform Commission meeting. A recap of her coverage can be seen below.