Woburn teachers and officials in the Massachusetts city say they have made significant progress toward ending the teachers' strike, but there is no confirmation that school will resume Monday after classes were canceled all of last week.The strike started Jan. 30 and Woburn's schools have been closed since then with teachers remaining on the picket line.Mayor Scott Galvin said he and the School Committee met with representatives of the Woburn Teachers Association from 10 a.m. Friday to 1 a.m. Saturday to negotiate.Both sides said a tentative agreement was reached on financial packages in the contracts for both teachers and paraprofessionals, but Galvin said the teachers and the city need to come to terms on a "return to work agreement."According to Galvin, Woburn teachers will not face any disciplinary actions from the city as a result of the strike. The mayor, however, is asking for the teachers union to cover $250,000 of the $270,000 in costs incurred by the city during the strike."The police details were just about $95,000, thereabouts," Galvin said. "Again, there are costs to the schools for having some of the staff come in when they wouldn't have had to come in.""The city wants to extort us for $250,000," said Woburn Teachers Association Secretary Eric Scarborough. "We were willing to pay some money, and then also make generous donations to various charitable organizations throughout the city."The $250,000 sought by the city is separate from the fines a judge has ordered the Woburn Teachers Association to pay to the state.Negotiations are set to resume between 10 a.m. and 12 p.m. at Joyce Middle School.