With talk of a strike intensifying, the education group A+ Schools hopes to pressure the Pittsburgh Public Schools and its teachers union into settling their 6-month-old contract dispute.

The Downtown group has printed 4,000 postcards demanding a contract, and it's inviting parents and others to send them to school Superintendent Mark Roosevelt and Pittsburgh Federation of Teachers President John Tarka.

The postcards come stamped and addressed; senders only have to sign them and drop them in the mail.

The postcards urge Mr. Roosevelt and Mr. Tarka "to resolve the issues related to a teachers' contract in a way that avoids a strike and ensures that educating our children progresses without interruption." The cards also urge the two to "ensure that kids are never used as a bargaining chip."

Carey Harris, executive director of A+ Schools, yesterday said she was looking for volunteers to help distribute the cards.

"We're concerned. This has gone on longer that we would have liked," Ms. Harris said of the labor dispute.

Negotiations resume tomorrow, and another session is scheduled for Friday. The union has set no deadline for a strike, but fears have been escalating because of little good news from the talks.

"From what I understand, they're still pretty far apart," Ms. Harris said.

The PFT represents about 2,800 teachers and other professionals, about 600 aides and about 60 technical-clerical workers in three bargaining units, which have been without contracts since June 30. Stumbling blocks include salary and various non-economic issues.

"Certainly, we're working very hard to get a resolution to these negotiations," Mr. Tarka said yesterday.

In mid-October, the union rejected Mr. Roosevelt's call for binding arbitration, saying it couldn't accept the proposed format.

Later that month, union members voted 2,666 to 234 to authorize a strike, if necessary.

Mr. Roosevelt said community input is welcome and added that the district as much as possible will heed calls to be open-minded and flexible.

"We hear that, and we will try," he said. But he added: "I cannot make a decision that will result in our having to raise taxes."

Mr. Tarka said he had received an electronic version from several residents and responded with e-mails saying the union would continue to work to resolve the dispute.

"I appreciate the fact that citizens want to express their opinion," he said.