Across the Philadelphia School District today, teachers and principals will be wearing the color red. Tomorrow they'll don blue.

The show of colors is not an end-of-year stunt, nor has it anything to do with patriotism. It's a show of solidarity by the unions representing teachers and principals.

The 16,000-member Philadelphia Federation of Teachers - whose color is red - and the 850-member Commonwealth Association of School Administrators - whose color is blue - have been drawn together in opposition to how district Superintendent Arlene Ackerman is treating them, said Michael Lerner, CASA president.

Attempts to reach Ackerman through the district's Office of Communications were unsuccessful.

"I think, basically, my members have come to understand that while there are many issues that separate us and the PFT, there is a big issue that brings us together - Dr. Ackerman," Lerner said.

"I think that it's important to note that PFT and CASA members really share the same mission, and that's to educate kids and improve the quality of schools," said PFT President Jerry Jordan.

"It's the time for us to spend our energy working together to make sure we achieve that mission," he added.

Ackerman, who took the helm of the district last June, has upset the union leaders and some members in recent weeks by pledging to terminate those who are rated unsatisfactory.

The comments come at a sensitive time, as the district is negotiating new collective-bargaining agreements with both unions and three others that represent school police, cafeteria employees and blue-collar workers.

The names of a handful of principals who will not be returning to their schools have leaked out, but Ackerman has neither confirmed those names nor said which principals would be fired and which would be transferred.

Lerner said that he was concerned that Ackerman's silence on the matter could taint all principals who transfer for any reason.

Ackerman, he said, "blew a golden opportunity" to forge strong working relationships with the unions due to her harsh comments.

"The fact of the matter is, you might think she would say, 'We have had problems but we are working them out with the help of yeoman principals and teachers,' " Lerner said. "But she did not say that. She said she is going to fire people."

Ackerman, during last Wednesday's School Reform Commission meeting, said that she was disappointed during her first year that some adults do not put children first.

"It's frustrating that sometimes the adult agendas at every level of this organization - sometimes in the district [and] outside of the district - continue to make this a challenge," she said.

At 7 this evening, the PFT will hold a special membership meeting at Temple University's Liacouras Center.