An ocean of teachers in red union t-shirts filled the streets downtown for a protest outside Chicago Public Schools headquarters on Monday afternoon.

Earlier, they picketed outside their schools.

This was day one of the first teachers strike in 25 years in Chicago, but what motivates individual teachers to rally in the streets may not be what negotiators are discussing behind closed doors.

“They’re down to two issues that we can finish,” Mayor Rahm Emanuel has said. Those issues have to do with how teachers are evaluated and job security in the face of school closings and shake-ups.

But if you talk to teachers with picket signs, they say they’re on strike for things that go far beyond what’s being talked about at the bargaining table.

Common complaints

At Attucks Elementary on the city’s South Side this morning, picketing teachers chanted for air-conditioning.

“Some of the resources that we have in the schools are inadequate. They know it, and we know it,” said Christian Nze, a special education teacher and strike captain.

Behind him, teachers shouted, “98 degrees! 120 degrees in the school!”

On the North Side, Alyese Faibisoff, a teacher at Armstrong Elementary in the Rogers Park neighborhood, says she has to be more than a teacher.

“I went and bought 16 ice packs to keep in my room so I don’t have to I buy band aids. We don’t have a nurse here . We don’t have a full-time social worker here either. And that’s dangerous.” About 1500 students attend Armstrong. “If you want the children to learn, all of their needs need to be met. Not just the academics. There’s a social, emotional piece,” Faibisoff said.

The big issue for lots of teachers is class size.

“Last year, third grade, I had 42 students. From the first day of school until two weeks before school ended,” said Cheryl Collins, a teacher at Ashe Elementary on the South Side.

Union president Karen Lewis has talked a lot about these issues. And she talked about them again last night when she announced teachers were walking off the job.

“Class size matters. It matters to parents. In the third largest school district in Illinois, there are only 370 social workers, putting their case loads at over 1,000 students each Lewis said at a press conference Sunday night.

The union knows these are issues that matter to teachers and to parents, who they need on their side. And union leaders are skillfully putting those issues front and center in their public statements.

But teachers’ everyday issues don’t appear to be the major sticking points the district and union are haggling over; and they may not find any place at all in the new contract.

It’s about the money

Chicago Board of Education president, David Vitale, has been part of negotiations for the district. He says class size will remain exactly the same in the new contract.

And air conditioning?  “You know, we frankly agree with them on air conditioning. We’d like to have all of our schools air conditioned,” Vitale said.

“The problem is, that’s a very expensive proposition. It takes money. And if we’re going to spend it on air conditioning, guess what we’re not going to spend it on. People.”

He isn’t just talking about teachers’ salaries. He’s also talking about people like social workers or additional teachers to reduce class sizes.

Still, for many teachers, there’s something cathartic about striking over issues they deal with day after day, year after year.

One South Side teacher said every teacher in his school was on the picket line this morning. For hours, cars honked in support, parents brought coffee.

He said he felt empowered when he heard the union president say on TV last night that teachers would be walking out. It’s not that he wants to strike, he said. It’s that finally people have to hear from teachers about their very real challenges.

But  it remains to be seen whether the things that matter most to teachers, the things many believe they’re striking over, will end up in the final contract agreement.

Contributing: Natalie Moore and Odette Yousef