Classes in the Downingtown Area School District have been canceled and teacher picket lines are scheduled to go up at 10:30 this morning after long negotiations Sunday failed to reach agreement.

The 11,730-student, 13-school district is Chester County's largest, and this would be the first teacher strike there since 1980. No new talks have been scheduled. Updates will be posted on the district Web site, www.dasd-adm.org, and on a hotline, 610-450-3263, that is to be updated regularly.

Sunday's talks, which went past midnight, brought the sides closer on health-care issues and left them less than $2 million apart on salaries as calculated over a four-year period. The school board said its final offer includes a 4.4 percent raise in the first year, with raises of 4.5 percent, 4.5 percent, and 4.6 percent over the next three years. The union held out for a 4.85 percent raise in the first year, with proposed increases over four additional years of 4.85 percent, 4.85 percent, 4.6 percent, and 4.6 percent.

The union offered to call off the strike if all differences were submitted to an arbitrator. The board said it did not want to leave the final decision up to an outside party.

By state law, the strike would be limited to the number of days that would allow students to get in 180 instructional days by June 15. The state Department of Education will decide how many days that would allow the teachers to strike. Paul Gottlieb, a Pennsylvania State Education Association staffer and negotiator for the teachers union, said estimates were that the stoppage could last from 12 to 22 days. If there is no settlement by then, the sides would enter nonbinding arbitration.

School board member and negotiator Alice Johnson said the board wanted the teachers to go through nonbinding arbitration.

"It is unfortunate that they have decided to go forward with their intent to strike," Johnson said. "The board believes that it has offered a balanced contract that compensates teachers without placing additional heavy burdens on the district's taxpayers."

Gottlieb said that only agreement to binding arbitration would have headed off a strike as "the school board could ignore" nonbinding recommendations. The district, Gottlieb said, is fifth among the 12 Chester County districts in tax rate and third in property values, yet is 10th in teachers' pay over a career. "We're trying to catch up with the rest of the county in terms of where we are on the pay scale," he added.

The current starting salary is $43,330 and the top salary is $81,815.

Gottlieb said that the district has run up a surplus this year of $8 million that could be used to settle the contract. Johnson said the rapidly growing district, which will have to build a third middle school soon, is facing "financial challenges . . . in the years to come" and does not want to spend more.

Business Manager Richard Fazio said the district has a contingency fund of 8 percent that normally is rolled into the next year's budget. If the district has no unexpected expenses, that would lead to a surplus in June of about $13 million, he said.

For one district parent, even one day of a strike would be too many. "I'm very upset that this is happening," said West Pikeland resident Barbara Hurt-Simmons, president of the district's Joint Home and School Council and the mother of two children in its schools.

"I would like to see a quick, thoughtfully worked-out settlement," she said. "They're holding the students hostage. They need to get this resolved."

Downingtown is the only district in the Pennsylvania suburbs where a teacher contract remains unsettled.

Contact staff writer Dan Hardy at 610-701-7638 or dhardy@phillynews.com.