The strike includes about 25,000 members of the Chicago Teachers Union and 7,000 support staffers belonging to another union. City officials said Thursday they planned to provide lunch and activities for the more than 300,000 students in the district, the nation's third-largest.

United CU's strike loan offers members up to $300 per week (capped at $1,200 for duration of the strike) at 5% interest. The loans can be made after five days on strike.

After the strike ends, members must start paying at least $50 a month on their loans deducted from their paycheck deposits. They have an incentive to pay off their loans because the Illinois Federation of Teachers has promised to reimburse members for their interest payments once the loans are paid off.

Dolphin Harris, the credit union's chair and a retired educator, said the credit union has helped members in past strikes but not with a loan structured for that purpose. "It was nothing hard and fast, and it had a lot of restrictions," he said.

The strike is Chicago's first major walkout by teachers since one that lasted 27 days in 2012.

About 90% of its members are current or former school employees. Teachers who are currently not members of the credit union can become eligible by opening a savings account with a $25 deposit.

How many loans does the credit union expect to make?

"We don't have the foggiest idea," Harris said. "It it's a prolonged strike we'll obviously have more of them."

Besides the interest guarantee from the union, another reason the credit union has confidence in offering the loan is that its members are disciplined savers. Most of them already participate in the credit union's "Summer Savings" account to put aside money to cover the lean weeks when school is out.

The teachers' strike began as 49,000 GM workers prepared to vote on a new contract Saturday.

Credit unions with ties to employees of General Motors have been active in offering strike loans to those workers, who have been out since Sept. 15. Those workers went from making about $1,200 a week from GM to $250 a week in UAW strike pay.

Credit unions with ties to teachers also stepped up last year when education uprisings started in West Virginia where teachers won a 5% pay raise after a nine-day strike that ended in March 2018. Later that spring teachers staged actions in Kentucky, Arizona and Oklahoma.

When Oklahoma teachers walked out in April 2018 over low pay and classroom spending, Oklahoma Educators Credit Union ($161.3 million, 14,622 members) posted on Twitter showing employees at a table outside the state capitol in Oklahoma City handing out bottles of water and stickers with the credit union's logo. By the third day of the walkout they had given out 4,500 bottles of water.

Although many credit unions like United CU have adopted more generic names, there were still 295 credit unions with "teacher," "school," "educator" or "education" in their name as of June. Together they had $67.6 billion in assets and 4.9 million members.

United CU has been open to residents of Cook County for about seven years, and is now expanding its branches to better serve its dispersed membership. It started the year with three branches, and recently opened a fourth at the Chicago Teachers Union office — 2.5 miles west of city hall. A fifth branch is scheduled to be opened by year's end.