06/01/2012 03:54 pm ET Updated Jun 01, 2012

Chicago Teachers Union Strike Vote To Be Held Before School Year's End (VIDEO)

Updated story

After months of conflict between Chicago Public Schools staff, administration and the city, the Chicago Teachers Union announced Friday that it will conduct a strike authorization vote before the current school year's end.

The balloting will begin on Wednesday, the Chicago Sun-Times reported Friday, and will continue over the course of several days.

The union has been threatening to strike since last summer to protest changes in the school day, their pay metrics and the way their performance is evaluated. This week, they requested a three-member panel review proposals for both sides, the first step toward a strike, according to the Chicago Tribune.

The strike vote will be the latest move in the battle between teachers and administrators that has raged on for over a year, marked by failed contract negotiations, objections to new teacher evaluation models and pushback against the city's initiatives to lengthen the school day.

On Thursday, CPS blamed the union for the $34 million Department of Education grant it will forfeit Friday, NBC Chicago reports. The grant stipulated that the union and the school district had to agree on a plan to implement the merit-based Teacher Incentive Fund within two years.

CPS blamed CTU's unwillingness to negotiate for the loss, but they aren't the only ones pointing fingers. The union slammed the pay program in a statement released Friday:

"Public school educators are tired of being bullied, belittled and betrayed," the release read. "CPS' contract proposals will lead to larger class sizes; more children being expelled; and lower achievement levels among all students."

State law requires worker strikes to be put to a vote, and at least 75 percent of union members must approve the measure before work stops, according to ABC Chicago. Special education teacher Oscar Ortiz told the station that "the strike talk is very real."

In April, CTU President Karen Lewis said teachers were "fed up," and that teachers at more than 200 schools supported a protest that included leaving the workforce in a series of "mock strike votes." At all schools that conducted mock votes, support for a strike registered at or above 80 percent, with many schools seing 95 percent or more of the teaching staff expressing interest in a protest.

In an interview with Fox Chicago, CPS chief Jean-Claude Brizard said the district wants to give teachers raises, but cannot afford the 30 percent increase over the next two years that teachers have requested. Brizard also pointed to the lost grant money, which he says could have helped offset those costs,.

"It's $35 million that will go to teachers to pay people who are working in hard to staff schools, hard to staff subject areas, no strings attached," Brizard said (See video above). "$35 million for pay for teachers, some getting as much as $15,000 more in their paychecks."

Brizard pleaded Friday that the union hold off on going on strike because an independent reviewer is currently reviewing offers from both sides in the ongoing negotiations, NBC Chicago reports.