The School Reform Commission's chair and its longest-tenured member tendered their resignations Wednesday, a surprise move that will have major implications for the Philadelphia school system.

Stepping down are Chairwoman Marjorie Neff, a former School District principal, and Commissioner Feather Houstoun, who formerly ran the William Penn Foundation and served as a top official in Pennsylvania and New Jersey state governments.

Neff's resignation is effective Nov. 3 and Houstoun's Oct. 14, the day after the next SRC meeting.

The terms of both were to expire in January, and neither was expected to be reappointed. The term of Commissioner Sylvia P. Simms is also up in early 2017.

Even though Neff and Houstoun had only months left in their terms, their departures shocked many. Some of their fellow commissioners learned of the news only a few hours before it was made public.

Neff said the commissioners had agreed it was best to stagger the arrival of new members. Her replacement will be named by Mayor Kenney "in the coming weeks," Kenney said in a statement. Houstoun's successor will be chosen by Gov. Wolf and must be confirmed by the Senate, a process that is unlikely to be quick.

While Neff said she was honored to serve, it was clear that the position was at times frustrating for her.

"On the macro level, the problems are so big and intransigent that it's difficult to see all the small victories," she said. "I'm not sure that my skill set - my temperament - is particularly suited for this large, very slow-moving kind of change."

Neff said she would continue to fight for the district, particularly on funding issues.

Houstoun said her decision to resign now was dictated by "entirely personal circumstance."

"It became untenable to give the SRC the kind of bandwidth that it deserves," she said. The timing also worked, she said, because the district is in much better shape than it has been at any other time during her tenure.

Neff was named to the SRC in 2014 by Mayor Michael Nutter shortly after she retired as principal of Masterman School, a district magnet. She became chair in early 2015, when Wolf stripped Commissioner William J. Green of that title.

She has consistently voted against charter-school expansions and granting new charters, saying the district is not in a financial position to do so, despite enormous pressure from some politicians.

Green has sued to regain the chairmanship, but has said he takes issue not with Neff's leadership but with the governor. A Commonwealth Court hearing on that suit is set for this month.

Houstoun was named to the SRC in 2011 by Gov. Tom Corbett and was quickly called upon to help steer the district through an unprecedented financial crisis. Shortly after she joined the commission, the school system nearly ran out of money, and her public-finance expertise was crucial to making a path to fiscal stability.

Houstoun is often the swing vote when the SRC is divided.

She said she has relished the job, and working on a board made up of five people with very different backgrounds.

"Even though there were changes of SRC commissioners, there was an enormous amount of mutual respect for each other's points of view," Houstoun said. "It really made our decision-making much richer."

Houstoun's and Neff's departures raise questions for the SRC going forward. The new commissioners will help negotiate a contract with the Philadelphia Federation of Teachers, which has been without a pact for three years.

But some education-watchers worry if the SRC will even have a quorum for some votes in the near future. Simms, Green, and Commissioner Farah Jimenez remain, but Jimenez often recuses herself from votes because of possible conflicts of interest.

Others used the moment to renew calls for an end to the SRC, created in 2001 as part of a state takeover of the district.

City Council President Darrell L. Clarke said Neff's and Houstoun's resignations ahead of the expiration of their terms should be the starting point for a conversation about returning the district to local control.

"I have long believed that this conversation must begin with consensus around the fact that state control of the School District of Philadelphia has been a failed experiment with severe consequences for all Pennsylvanians," Clarke said in a statement.

Philadelphians in 2015 endorsed a nonbinding resolution calling for abolition of the SRC.

Kenney, who has publicly supported ending the SRC, but only when the district is more stable, seemed to dismiss any calls to end the SRC imminently. He said he was in talks with potential successors for Neff.

"I believe that any future commissioner must be fiercely dedicated to making the SRC a highly functioning governing body that strengthens our schools, and supports our students and educators," Kenney said in a statement.

Jeff Sheridan, a spokesman for Wolf, said the governor had "already begun the process to select a replacement for Feather, but no final decision has been made at this time."

There was no timetable for when Houstoun's replacement might be nominated, Sheridan said.

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