The extensive and valuable art collection owned by the Philadelphia School District should be freed from a decade in storage and publicly displayed once more, the city controller told the school superintendent Wednesday.

More than 200 pieces, including paintings by the noted Philadelphia-area artists Henry Ossawa Tanner and Walter Baum, were removed from city schools in 2004 when Superintendent Paul Vallas said the district lacked the capacity to properly safeguard or maintain the art.

The works, valued at $3.8 million, have remained locked in an art-storage facility since then.

The School Reform Commission was poised to sell some of the pieces to generate cash last year, but decided to shelve that plan. Commissioners said the work was too important to the district's history to sell.

In a letter sent to William R. Hite Jr., Controller Alan Butkovitz upbraided the district for a "lack of oversight" of the art over the years, and exhorted officials to "display the artwork for all to enjoy."

Over the years, some of the works have disappeared, as have records for others.

Butkovitz suggested that the district partner with organizations such as the Philadelphia Museum of Art and the Philadelphia History Museum at the Atwater Kent to explore ways the pieces might be displayed.

Fernando Gallard, district spokesman, said officials have been in talks with "a number of art organizations" over the last several months to do just that.

"We've asked them to help us identify ways to display the art, and to create some revenue-generating opportunities," Gallard said. "Those conversations are still ongoing."

Marilyn Krupnick, a retired district teacher, has long fought to remove the works from storage and have them displayed publicly. Krupnick taught at Woodrow Wilson Middle School in Northeast Philadelphia, where many of the most important works were kept.

Finding a partner to display the works has been tough, said Krupnick, who has reached out to some institutions herself. Organizations would have to have the resources to restore, secure, and display or store the works themselves.

But Krupnick remembers leading students on tours of the building, teaching students about the paintings and their history. The art mattered, and students treated it with respect, she said.

"We have to get the art back into the public eye," Krupnick said Wednesday.

Other local school systems have found themselves in similar positions. In 2011, the William Penn School District announced plans to sell a Baum work to raise money. The Quakertown school system has its Baum collection in a permanent exhibit at the high school. The Souderton Area School District used its art as the centerpiece of a fund-raiser.