UPDATED: 8/31/2012 6:15 a.m.

CHICAGO (CBS) –Chicago teachers will go on strike Sept. 10 if their negotiators cannot hammer out a new contract with the Chicago Public Schools system before then.

On the CBS 2 Morning News on Friday, Chicago Public Schools Chief Jean Claude Brizard said talks are scheduled this weekend and he hopes a deal will be reached before the deadline.

“We have to get this thing done,” he told CBS 2′s Susan Carlson and Kris Gutierrez.

On Thursday, CTU President Karen Lewis blamed CPS officials for dragging out negotiations, which hinge on pay increases and benefits and other issues.

“We have said from the beginning, we’re tired of being bullied, belittled and betrayed,” she told reporters during a Thursday evening news conference after the Chicago Teachers Union’s House of Delegates voted unanimously to set the strike date.  “We continue to be vilified and treated with disrespect.”

If teachers walk off the job, it will be the first Chicago teachers strike in 25 years.

LISTEN: WBBM Newsradio’s Bob Roberts Reports

Contract negotiations are expected to go throughout the weekend. Jean-Claude Brizard, the CEO for CPS, issued a written statement warning that the impact would be severe on Chicago’s 350,000 students.

“If our priority is our kids, then strike should never be an option. That’s why we need to take advantage of each of the next 11 days and work until we reach a fair resolution for our teachers that will allow our kids to stay in school where they belong,” Brizard said.

The teachers union already had filed a 10-day strike notice Wednesday, which made Sept. 10 the earliest date to walk off the job. That prompted CPS administrators on Thursday to release a plan to keep 145 schools open if a strike occurs.

The schools would be open during the morning for four hours (8:30 a.m.-12:30 p.m.), Monday-Friday, the CPS said in a news release.

CPS said it will use buildings with air conditioning, including gyms, cafeterias and computer labs.

LISTEN: WBBM Newsradio’s Nancy Harty Reports

Students would get breakfast and lunch, but no instruction. CPS says the students can play sports, read, write, create artwork and work on computers.

Facilities would be run by central office staff and other non-union workers. The district says the student-staff ratio would be capped at 25-to-1.

Chicago Park District summer camps and public libraries would be utilized in what is being called “The Children First Plan.”

“We need to be prepared to provide students with the services they need should [the teachers union] leaders decide to strike,” Brizard said.

At first blush, parents are not happy and some may just keep their kids home or have to put them in day care.

“If nothing else there is pbskids.com, there is ABC Mouse, there are websites that you can still give your children instruction,” Natasha Trotter Gordon told WBBM Newsradio’s Bernie Tafoya. “I would rather do that as opposed to having them look at each other for four hours and have a snack.”

Parent Kevin Dortch of Englewood works two jobs and doesn’t know what he’ll do with his son Dominick if a strike occurs.

“Sometimes it feels like the children are used as a political football,” Dortch tells CBS 2’s Brad Edwards.

LISTEN: WBBM Newsradio’s Bernie Tafoya Reports

According to the district, a strike would impact students in several areas:

• They would not be given any classroom instruction.
• Fall sports practices and games would be canceled, affecting about 11,000 student athletes
• Seniors applying to college would not be able to send transcripts, ACT scores or obtain teacher recommendations
• Juniors would miss practice tests for the ACT.

However, later on Thursday, CPS said it has asked the Illinois High School Association for a waiver to allow students to continue to practice and compete in fall sports.

“This is an effort to preserve current opportunity for CPS student-athletes to succeed during this season as well as future opportunity for sports-based college scholarships,” CPS said in a news release.

IHSA bylaws and policies prohibit student participation in interscholastic activities in the event of a strike.

CPS has asked whether teams can continue to hold practices if a properly credentialed coach is in place to ensure safety. About 90 percent of certified CPS coaches are CTU members.

No actual strike date has been set. The union’s House of Delegates plans to meet Thursday, and could set an official strike date at that meeting.

Wednesday afternoon, CTU President Karen Lewis told reporters there’s been so little progress in ongoing contract talks, that the union had no choice but to act.

Lewis said, “This is a difficult decision for all of us to make, but this is the only way to get the [Chicago Board of Education’s] attention.”

Teachers are looking for salary increases and job security, among other issues.