The School District of Philadelphia has appealed a judge's ruling blocking the sale of five former school buildings to a Maryland real estate developer.

The appeal to Pennsylvania's Commonwealth Court is in response to a decision last month by Common Pleas Court Judge Nina Padilla-Wright, who denied a petition by the school district to complete the sale.

Padilla-Wright gave no reason for the denial in her Feb. 17 order, and the School District made no arguments in its appeal.

Filed Wednesday, the appeal is the latest development in Concordia Group's efforts to complete its $6.8 million purchase of the buildings, which once housed Germantown and Charles Carroll High Schools and Robert Fulton, Walter Smith, and Abigail Vare Elementary Schools.

The School Reform Commission included the buildings among the 11 shuttered schools it voted to sell in September 2014. Some residents of Point Breeze, where Walter Smith School was located, had hoped its building would be acquired by a charter school operator and challenged the portfolio sale.

Deborah Cianfrani, a lawyer representing the Point Breeze Community Development Coalition, argued last year that the school district was violating its rules for open bids by not selling the properties individually. The district responded that the properties were being sold privately, rather than being put to bid, which only required a judge to sign off on the transaction. That put the decision in the hands of Padilla-Wright, who rejected the deal after seeking public comment.

Concordia co-founder William J. Collins did not return calls seeking comment Thursday. The Bethesda company also is working with local developer Greg Hill to redevelop the Mount Sinai Hospital site in South Philadelphia into 95 townhouses.

District spokeswoman Raven Hill had no comment Thursday about the appeal.

Cianfrani said her clients had resumed their efforts to interest a charter-school operator in acquiring the Walter Smith building. "They're trying to work with different developers to purchase the school for educational purposes," she said.

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