CHICAGO –- Two weeks before teachers here went on strike, shutting down the third largest school system in the nation, a teenage boy was shot and killed in a rough neighborhood on the South Side.

At Morrill Math and Science Specialty School, the shooting prompted teacher Monique Redeaux to scrap her regular social studies lesson, a unit on Christopher Columbus. Instead, she guided her seventh- and eighth-grade students through a discussion on violence and inner-city poverty.

The boy who was killed had been enrolled at the school the previous spring, and several of Redeaux’s students were with him when he was shot. Some felt vulnerable to potential retaliation amid talk that the shooting was perhaps gang-related. Even those who had not known him were shaken and disturbed.

At Morrill -- a sturdy brick building in an area littered with boarded-up homes -- nearly all of the roughly 800 students are black or Latino, and 98 percent qualify for free or reduced lunches, meaning they are poor or close to it. Every day, Morrill teachers compete with hunger, homelessness and trauma for the attention of their students. Kids show up having seen relatives slain or hauled off to jail. They sidestep syringes on cracked sidewalks, and they do their homework inside cramped houses with drafty walls, leaky roofs and the sound of gunshots crackling outside.

For students, the death of a former classmate was at once shocking and commonplace. “These are the issues that we’re dealing with,” Redeaux says.

She tells me this by way of explaining her opposition to the teacher evaluation system the Chicago Public Schools system has been moving to impose on teachers, one of the most contentious issues dividing the administration from the union. In essence, the job security of teachers will rest upon their ability to show gains in student achievement on standardized tests. Those who fail to deliver risk losing their jobs.

Like most, if not all, of the teachers manning picket lines here in the past week, Redeaux contends this system is unfair and governed by principles that only make sense so long as you have never been inside her classroom to witness the challenges of trying to educate young people in a crime-ridden, poverty-stricken inner city neighborhood.

She is no fan of standardized tests, she says, because they undermine the sort of creativity a teacher in her situation requires: one built on understanding that the Monday after a former classmate has been murdered, students might be disinclined to think about European explorers setting out for bounty in the New World half a millennium ago.

The evaluation system school district authorities want to put in place here is premised on the assumption that progress on standardized tests reflects quality instruction, while poor test scores reflect unsatisfactory work by teachers. For Redeaux, this assumption collides with reality. For one thing, research has found the methods used to evaluate teachers are typically flawed. But more importantly, she maintains, her students are confronting challenges far beyond the imperative to memorize historical dates, and that constrains their performance, rendering standardized tests a bogus measure of their achievement.

“They’re dealing with issues like, ‘I’m hungry', or ‘I don’t necessarily know where I’m going after school’,” she says. “There are things that happen in this neighborhood all the time. And you have to take time to discuss those things. Standardized tests don’t account for any of that. They tell us about the zip codes people live in, and how much poverty there is. To hold us accountable for all of those other factors is unfair. To think that the things that are happening in the streets are not going to spill over into the classroom is very callous and unreasonable.”

On the most basic level, the teacher strike in Chicago is about a labor contract and the details of its provisions -– the range of compensation, the hours to be worked, the processes governing hiring and firing. That dispute appears to have been resolved, with a framework in place for a new contract that could put teachers back in the classroom as soon as Monday, pending a union vote Sunday.

But in a broader sense -– the sense that makes Chicago not merely the scene of a labor dispute, but the venue for a battle over the principles shaping American public schooling -- the strike here is about how to assess the fundamental worth of teachers, and how to address disappointing educational results.

From Los Angeles to Cleveland to Boston, teachers unions have recently agreed to deals that make their job evaluations subject to the achievements of their students on standardized tests. Not in Chicago. Here, teachers have challenged this trend, portraying their strike as no less than a fight to prevent the dismantling of public schools through a statistically driven effort to declare them failures.

“What the union sees, and what the public is beginning to see, is it’s about the future of public education,” says Tom O’Brien, a social studies teacher at Westinghouse High School on the West Side. “The country is watching us.”

That much seems clear. Even as the strike appeared to be nearing an end on Friday, union organizers prepared for an influx of thousands of sympathizers from Wisconsin and elsewhere on Saturday for a rally. Teachers unions across the country have been monitoring events here given the aggressive push-back to the so-called educational reform agenda, which has featured a greater focus on standardized tests and a growing role for charter schools.

Nationally, the reform movement has gained considerable momentum, spurred by the Obama administration’s Race To The Top initiative –- $4.35 billion worth of grants conferred by the Department of Education to states that tie teacher evaluations to standardized test results while expanding funding to charter schools.

Here in Chicago, Mayor Rahm Emanuel -- formerly President Barack Obama’s chief of staff -- made educational reform a primary part of his program, leading to open hostilities with the teachers union. The union depicts him as a corporate shill who is doing the bidding of the business interests who financed his successful mayoral campaign: His real goal, teachers say, is to privatize the system by shuttering public schools and diverting students to profit-making charter schools.

Charter schools are generally not unionized, and they pay much lower wages than public schools – just above $50,000-a-year on average in Chicago, as compared to about $75,000 for public school teachers.

“RAHM SAYS NO CORPORATION LEFT BEHIND,” declared a hand-lettered sign at a union rally that wound through downtown streets Thursday afternoon.

Emanuel has presented himself as an advocate for Chicago’s children, who too often get left out of policy considerations when the city negotiates with teachers. He has cited the school system’s poor performance –- one-quarter of public school students failed to graduate from high school, and a third of fourth-graders failed to meet reading standards -– as evidence that reforms are required.

Last year, he revoked a 4 percent raise that had been promised to teachers under their existing union contract, declaring that under that deal students “got the shaft.” He has pushed to make student performance on standardized tests count for 40 percent teachers’ evaluations, a posture that contributed heavily to the union’s decision to strike, while casting this as a simple matter of accountability.

The teachers counter that they are effectively getting stuck with accountability for complex social problems that extend far beyond their control. No one in Chicago runs the risk of losing their job for failing to supply enough low-income housing. No one must satisfy a numbers-based standard for increased employment in impoverished communities. No one is on the hook to ensure that students show up well-fed and well-rested. All of these issues roll down to teachers, they say, directly influencing conditions in their classrooms. Yet they alone find themselves having to answer for the sole measured result: achievement on test scores.

“We’re definitely getting the brunt of it,” says Brandon Johnson, a social studies teacher at Westinghouse High School on the West Side. He notes that the school system last year documented 17,000 cases of homeless students – “that’s only the documented cases,” he says – yet it has fewer than 400 social workers.

“They come to us with all of these challenges, and we’re up for them, but we’re not being given the tools,” he says. “If we can’t offer them basic services, how can we expect kids to excel?”

'WHAT ARE YOUR GOALS?'

Carla Roberson has no patience for that kind of talk, dismissing the idea that standards of achievement for poor inner city kids must be discounted for social problems. She is incensed by the notion that people paid with public tax dollars to teach young people should be entitled to a pass for lousy results. This is insult to injury, she says: It amounts to punishing those born into lesser means with a lifetime sentence of lesser expectations.

“Every child has the potential to learn, no matter what economic or social or racial background they come from,” she says. “You have to hold the teachers accountable, period, point-blank. They have to be able to break it down and get their students to digest it and understand it. Children want to learn.”

Roberson’s disgust for the teachers’ position stems from her own experience with Chicago Public Schools. She sent her daughter, Bianca, to an elementary school in the South Side suburbs, and was dismayed to see how little she was progressing.

She saw on a Web site that second-graders typically learn how to tell time, how to solve word problems involving time intervals, and how to do basic multiplication. “She was still barely doing addition,” says Roberson, 36. “I’m like, ‘I remember learning more than this'.”

When she went to school to discuss her concerns with Bianca’s teacher, a young woman with a class full of 28 students, Roberson was stunned by her reaction.

“She kept telling me she was just following the curriculum,” Roberson says. “I asked her, ‘What are your goals for this class by the end of the year? What do you expect that they will learn?’ She told me, ‘Oh, I’ll have to get back to you on that.’ And I’m like, ‘Excuse me? You should know by the time school started.’ When I saw she didn’t have a future goal, I knew I was in trouble.”

This is how Roberson came to send her daughter to a charter school, Learned Excel, a publicly financed, privately run institution that has substantially accelerated Bianca’s growth trajectory.

“When she got in that school, they were on it,” Roberson says. “They had homework. They were doing all these tests and assessments.”

At first, in her third-grade class, Bianca could not keep up. In public school, she had been a straight-A student, but at Learned Excel she strained to get Cs. Yet this was progress, Roberson says. Her daughter has benefited from a stricter regimen and the attention of teachers in classes half the size of her previous school. She needs standards that are measured and reinforced by the clear and definable goal of test scores.

“She rose to a higher level of expectation,” Roberson says.

To the teachers union, this sort of story is ominous -- not just for Chicago, but for the nation. Chicago now has more than 100 charter schools up and running, roughly twice as many as seven years ago. The Illinois Network of Charter Schools has its sights on enrolling 100,000 students in Chicago, roughly doubling the current number. Nationwide, from Los Angeles to New York, charter schools are expanding, finding a niche in poor areas in which schools are considered substandard.

The union portrays charters as well-connected businesses that are vacuuming up public finance for their profits while promising better results than they typically deliver. Worse, they are capturing money that would otherwise be going to public schools.

“They are trying to make money off the backs of poor people,” says Johnson, the Westinghouse High School teacher. “We see this as an incredible threat to the public interest.”

But to Roberson and other parents who have sent children there, charter schools are a blessing, offering an alternative to a public system that has let them down. She has no sympathy for the union position that more students going to charters comes at the expense of public schools.

“It’s just crazy to say, ‘Let’s just leave it the way it is, because if we change it, it’s going to mess up the whole system,’” she says. “We can’t sit back and say ‘no’ to more charter schools, or we’re going to stand for mediocrity. We have to take a step.”

As she sees it, the teachers union is using poverty and social strife as an excuse for its failure to deliver better results for Chicago’s young people.

“They need to be held accountable,” she says. “The teachers need to work with the leadership instead of fighting the system. Rahm Emanuel came to bring change to Chicago. Whether they want to fight against him and buck up against him, it’s going to happen. Either you’re going to get on the bus and ride on, or you’re going to get left behind. We can’t just keep letting these teachers perpetuate just getting by.”

In the Inglewood neighborhood on the South Side, Patricia Porter hears the talk that educational reform threatens to replace public schools with charter schools, and she hopes it will happen sooner than later.

“The whole system is failing,” she says. “It needs a total overhaul.”

A retired office worker living on a limited pension, she has raised three sons, six of her sister’s children (after her sister died), and now three of her sister’s grandchildren. The mantle in her living room is crowded with framed pictures of five of these children wearing shiny gowns at their college graduations, plus a portrait of Obama and the logo for the Chicago Bulls basketball team. On the armrest of her couch sits the latest report card for one of her sister’s granddaughters, now an eighth-grader at a charter school, IIT Math and Science Academy. It shows four As and a C.

The two public middle schools in the neighborhood were both dismal options, Porter says. They were aging and unsafe, with paint peeling off the walls and desks falling apart. Fights broke out in the halls, and classes were so crowded that teachers regularly hollered at students in frustration, she says.

At the charter school, order and respect reign, she says. The facilities are spiffy and new, with ample computers and white boards, plus audio and visual equipment.

“Kids are there for a reason, to succeed,” she says. “It’s like a wish come true.”

Porter has no interest in saving Chicago’s public school system. She wants to see a new one erected, one in which charter schools play a central role.

“The public schools are very much inferior to the charter schools,” she says. “It’s like, if you go to the store and see they’ve got a better brand with better quality, you’ll go for that. That’s what I did for my child.”

She describes the strike as “a power struggle,” in which the teachers are trying to preserve an arrangement that is wholly unfair to students: “I’m going to get my check whether you learn or not.”

STANDING UP

This, it must be said, is neither the typical tone nor substance one encounters from parents when walking the streets with striking school teachers on the march. Car horns honk relentlessly in a cacophony of support. Passers-by pump fists and shout out “Solidarity.” Many approach the teachers to say “thank you,” or “keep fighting.”

The teachers are clearly buoyed by this backing, reveling in the festivities. But when you talk with them, what comes across is a sense of dismay. They feel they are taking on not only a hostile city government but the accumulated results of years of financial neglect of the schools: Starved of resources, many schools are indeed struggling to offer a quality experience for students, and parents are embracing the alternatives on offer: charters.

To the union teachers, this is understandable and perhaps inevitable. Parents have little interest in contemplating the ideal structure of the school system -– an abstract conversation –- and great interest in getting their own children into the best schools available. Yet the teachers decry the results: a threatened dismantling of public education.

The more capacity gets added at charter schools, the more that active parents like Roberson and Porter will move their children to these programs. The public schools that otherwise would have educated these kids lose not only funding but also the advocacy and involvement of these engaged parents. This weakens those schools and strengthens the arguments of educational reform proponents, helping them accelerate their plans: It becomes easier to brand public schools “failures,” seemingly justifying their closure and laying the groundwork for the further expansion of charter institutions.

This is the future as described by striking teachers if the current course continues: expensive private schools for those able to afford them, charter schools for those with active parents, and scraps for everyone else, with schools that serve the poor essentially left to deteriorate.

What infuriates public school teachers is how they seem perpetually stuck playing defense, fending off criticism that their union is really just a racket to protect the jobs of its least motivated members, just as they must beg for resources in a time of scarcity -– not just social workers, but textbooks, air-conditioning, toilet paper and art supplies.

The focus on numerical standards is an insult, they say. It implies that they are not sufficiently dedicated to their jobs, that they do not spend nights and weekends planning lessons and grading papers, that they are loath to be graded on performance because they don’t want to work hard.

“We have no problem with evaluation,” says Redeaux. “We want constant feedback. We all want to get better at our craft. We’re always trying to master the art of teaching. We need to sit down and have that conversation.”

The strike has evidenced an extraordinary disconnect between the conversation on the picket lines -- where teachers speak of their dignity and the philosophy of assessment -- and the discussion inside the negotiating room, which has by most accounts centered on salary schedules, grievance procedures, and which teachers get dibs on new jobs.

The latter conversation is about to end, with a compromise across multiple issues. But the bigger conversation, the one about the future of public education, is probably here to stay. Indeed, it may well intensify as municipalities continue to reckon with red ink following the worst economic downturn since the Great Depression.

“I don’t think anybody’s gone into this with the idea that we can declare victory at the end,” says O’Brien, the Westinghouse teacher. “The bigger issues are not going to be resolved in the scope of a contract. That’s a discussion that will continue on for years. But if we don’t stand up, we’ll be dealing with worse going forward.”

Joy Resmovits contributed to this report from New York.