About 10 juniors and seniors sit in Joyce Randolph's history class at Wendell Phillips Academy, a predominantly black high school on Chicago's south side, wrestling with a question they have focused on for weeks. Just how revolutionary was the American Revolution?

Ms. Randolph, an animated teacher who doesn't brook lethargy in her class, pushes the students to elaborate.

"Give it to me in your own words," she exhorts. At this point, she isn't looking for answers as much as wanting to make sure they understand what she's asking.

"How can we write an essay if we don't understand the question?"

Finally she gets a response from one young man: "Did the Revolution bring about significant change?"

"Awesome!" says Ms. Randolph, as she points to another student. "Curtis, what does 'significant' mean?"

She's met with a blank stare. Silence.

It's one of the dilemmas for many of the new teachers at Phillips, brought in a year ago to try to turn around this chronically failing high school. They are determined to do higher-level work with their students but often run up against basic vocabulary and reading-comprehension challenges. At the beginning of the year, 27 percent of the freshmen at Phillips read at a third grade level or lower.

What's going on in the classrooms of this inner-city high school is part of one of the toughest – and most important – experiments in American education today.

Across the country, a new movement is taking root, backed by the Obama administration, that is trying bold and controversial new methods – a kind of shock therapy – to fix the nation's worst schools. These are the bottom 5 percent, the roughly 5,000 public schools that chronically underperform and that, in many cases, society has given up on.

They are the schools that produce the worst test scores, suffer the worst dropout rates, yield some of the worst violence in the hallways.

Turning them around could help save successive generations of kids who quit and often end up jobless, mired in poverty, or worse. It could also dramatically improve the nation's educational performance.

Experts say that fixing even a fraction of these schools would lift the nation's test scores and education rankings, since the bottom-tier schools so depress overall performance.

Yet achieving this won't be easy. These schools have resisted the best intentions and ideas of educational gurus for decades. Now comes a new effort, led by President Obama's reform-minded secretary of Education, Arne Duncan, who vows to turn around 1,000 of the schools over the next five years.

He's putting $4 billion of federal money into the quest, and the methods his department is backing aren't incremental. They range from revamping a school from scratch, with virtually all new teachers, to installing a new principal who will carry out major reforms.

It's an ambitious goal – and a risky one. The record on dramatically improving the worst-performing schools in the country that, like Phillips, seem mired in failure is dismal: One recent study put the success rate at about 1 percent.

It's also controversial. Teacher unions and those on the left worry about replacing most of a school's staff. Many on the right see it as a waste of taxpayer money for something that won't work anyway.

But advocates argue that there's no choice without giving up on the futures of a large chunk of the nation's students. And they claim that done right, turnarounds have a far better chance of succeeding than the record would indicate.

"It hasn't been done in this kind of thoughtful, comprehensive way in the past," says Mr. Duncan. "It's some of the hardest, most difficult work there is, but it's absolutely critical that we engage in this work. If we don't, we perpetuate failures."

* * *

Phillips Academy occupies an impressive building, with an ornate facade and marble columns, in the Bronzeville neighborhood of Chicago. It also has a substantial pedigree. Named after abolitionist Wendell Phillips, it became the first predominantly black high school in Chicago, in the 1920s, and boasts an alumni roster of notable African-Americans: among them, singers Nat King Cole and Sam Cooke, as well as poet Gwendolyn Brooks.

It once produced a skilled group of basketball players who formed the nucleus of what would later become the Harlem Globetrotters.

But for the past few decades, Phillips Academy has been more known in Chicago for something else: failure. Last year, the school was the second-worst performing high school in Illinois. Less than 5 percent of its students met state academic standards. It had an 49 percent dropout rate. Fights regularly broke out after school in the neighborhood, and parents did whatever they could to keep their children out of Phillips Academy.

So in mid 2010 the Chicago Public Schools, working with a local nonprofit group, the Academy of Urban School Leadership (AUSL), got approval for federal funds to make Phillips a turnaround project. The Department of Education (ED) agreed to give the school roughly $5 million in grants over the next five years.

Under the DOE's School Improvement Grants (SIG) program, districts seeking federal money to revive a school must choose from four options: school closure (while ensuring that former students attend a better school nearby); restart, in which a school is usually taken over by a charter operator; "turnaround," in which the principal and at least half the staff is replaced; and "transformation," in which the principal is replaced and a number of major reforms implemented. Technically, Phillips is using the restart model.

For AUSL, the school represented a new challenge. The group had been turning around failing schools in Chicago for the past five years, some with striking success. Howe School of Excellence (a K-8 school), for instance, raised the percentage of students meeting state standards from 43 percent to 67 percent in just two years.

But most of AUSL's projects are elementary schools. Phillips was a high school, and, by all accounts, high schools are the toughest to change. Kids come in already many years behind in learning. Behaviors are entrenched. The schools are large, and communication is often lacking among teachers across subject areas and grades.

To oversee the school, AUSL brought in one of its most successful school-turnaround administrators, Terrance Little, as principal. A cool-headed manager who banters easily with staff and students, Mr. Little certainly knew the challenge he would be facing: He grew up on the gritty streets of Chicago and attended a poor high school himself that was shut down. To this day, he lives in the same neighborhood as most of his students.

"I thought I was an intelligent kid until I got to college," says Little, recalling what it was like to be challenged academically for the first time.

His approach in the hallways and from behind his desk is decidedly no-nonsense. Though not physically imposing, he is not the sort of person students question. At Phillips, Little's word is law.

As part of the transition to the new school, Chicago school officials dismissed all the Phillips teachers. Little hired back only two of the original faculty, both ROTC instructors. He also mandated the wearing of uniforms – navy blue pants for both boys and girls, and shirts color-coded by grade.

On top of that, he instituted a dress code – no shirt, for instance, could be untucked. Students had to wear visible ID tags, and carry clear backpacks so security guards could see what was inside them.

Little altered the schedule to keep freshmen at school an extra hour each day, and instituted a tougher grading scale. He enforced a zero-tolerance policy on discipline. He removed iron gates in the stairwells that he thought made the school feel like a prison. "If students come back, and it looks like it did when they left, then right there you've started off on the wrong foot," says Mr. Little.

His by-the-book approach was perhaps not surprising, given what Little saw when he visited Phillips last year. He describes it as a "zoo." Students were spending more time in hallways than in classrooms, and when they were in class, chaos reigned.

"There was food fighting in the cafeterias, and kids were always fighting in the hallways," recalls Eric Darko, a soft-spoken senior from Ghana, as he builds a complex tower after school for a Science Olympiad. "It was horrible bad. We didn't learn anything." This year, he says, things are better. "The teachers are always on time and on track."

AUSL puts its teachers through a yearlong residency program or offers other specialized training. As a result, all the teachers at Phillips have signed on to a certain curriculum and follow common practices in the classroom. A note on the wall or chalkboard of every class lists the agenda and objectives for the day.

"Do now" items get students busy as soon as they enter the room. Students get an "exit slip" on the way out, in which they are queried about how well they understood the material. The idea is to make sure students know some things will be the same, no matter what class they're in.

"The 'Do Nows,' the agendas, the exit slips – it's all a great format," says Pete Retsos, a sophomore history teacher who left a job at one of Chicago's most prestigious private schools to work at Phillips. He also likes the school's approach to discipline, in which teachers simply send students who break the rules to the dean. It frees up teachers to just teach. "In a conventional [Chicago public] school, the teacher has to deal with a lot of behavior problems," says Mr. Retsos. "Students rule the classroom in a lot of Chicago schools."

Instructors at Phillips are adamant about not teaching to low expectations. In her class, Randolph uses a "document-based questions" curriculum, which asks students to examine historical papers for evidence. Originally designed for Advanced Placement students, it is a rigorous program that she believes pushes them to think critically. On the other hand, she notes, her class is still on the American Revolution in February, and they've been working with the same question for weeks.

"They have severe deficiencies, but that doesn't mean you stop challenging them or asking them to do what high school students should do," she says. "I'm giving up the idea that they'll know US history really really well, but hoping they'll be critical thinkers and have reading comprehension."

* * *

Though turnarounds have been going on in some form for years, the idea first catapulted to national attention a year ago, when the school board in Central Falls, R.I., announced it was going to dismiss the entire faculty at the local high school as part of a plan to revive the failing school. Teachers and many others across the country were outraged, union members and students held rallies, and the district ultimately reversed its decision. It agreed to keep the teachers on staff in exchange for changes, including longer days, a new evaluation system, and targeted professional development.

While the board's capitulation on firings seemed to represent a public victory for teachers' unions, the turnaround movement has only accelerated since then. Some 850 schools received federal SIG money last year. Even though the majority (about 70 percent) have opted for the least restrictive "transformation" model, some 20 percent are going with the "turnaround" approach, in which most of the staff is replaced. The remaining 10 percent are restarts and closures.

None of the turnaround initiatives has caused the kind of furor that Central Falls did. In December, Dennis Van Roekel, president of the National Education Association, the largest teachers' union, even appeared with Duncan in support of a turnaround school in Prince George's County, Md., that was replacing much of its staff.

Still, Mr. Van Roekel emphasizes that the turnaround model in general is one he opposes as harmful to both students and teachers (in the case of the Maryland middle school, the district had worked with the local union in formulating the plan).

"I don't think the research shows that when you take adults out who are part of what gives these kids continuity in their lives – I don't think this works," he says. "Yes, the culture has to change, but I believe the way you change the culture in the building is by bringing the people together to say what is it that we want. Culture can't be shifted from the outside."

No issue involving turnaround schools is more divisive than what to do with the existing teachers. Many turnaround experts – and a number of principals – argue that without replacing the staff, it is impossible to achieve the radical change that's necessary, or to get the adults to embrace it.

Unions and others say such wholesale turnovers often do away with the people who know the kids best, including many who are outstanding teachers. They argue that outside the big urban districts, it's simply not possible or practical to change the teaching staff. Parents, in particular, are often outraged to see teachers they love lose their jobs. Besides, some schools have managed to improve without replacing staff.

Little knows all the arguments. He faced intense opposition from the parents of Phillips students, some of whom were particularly outraged that many of the teachers losing their jobs were African-American and many of their replacements weren't.

"People said, 'You're firing these people?' But it ain't about the adults. School is about the kids," says Little. "If you bring too many people back, then it's not a turnaround. It's very difficult when you have a big mess to sort through to find the star. And the time and energy you'll put into that, and then you make a wrong choice? It can be disastrous.... We already have to break the mentality of the students. It's difficult if I have to break the mentality of teachers and students."

Still, when teachers are moved out, the process can be complicated as well as controversial. In Chicago, tenured teachers let go at a turnaround school have one year to find another job – about 70 percent of them do so – but in some districts, they're just reassigned to other schools. (The lack of job protection is one reason turnarounds in general, and AUSL in particular, are highly unpopular with the local union in Chicago, even though teachers at Phillips are unionized.)

And if there's no pipeline to bring in outstanding new teachers and principals, any effort to do turnarounds on a large scale is likely to either drain good teachers from other schools or simply run up against a paucity of qualified people. A recent analysis by The New York Times found that among eight states that accounted for more than 300 of the federal turnaround schools this year, an average of 44 percent retained their principal from the previous year.

The SIG guidelines allow schools to keep principals if they were hired within the past three years, but the data seemed to suggest a lack of talent available, at least at the administrative level.

"Part of it has to be making the tide bigger and investing in the training of teachers," says Timothy Cawley, a senior manager at AUSL. "If you're just rearranging the chairs, it doesn't make sense."

Mr. Cawley believes the model that AUSL has created is ideal. Its teacher residency program benefits by ensuring that teachers go to high-needs schools, where they serve with other teachers who share their approach. They continue to work closely with AUSL coaches. The schools benefit because they don't need to recruit so many teachers, who in turn embrace what the principal is doing. "It gets off to a faster start," says Cawley.

More programs are springing up to train staff to handle troubled schools, including one at the University of Virginia's Curry School of Education, which helps experienced principals get the skills they're likely to need to run a turnaround project.

Another group, New Leaders for New Schools (NLNS), headquartered in New York, is focused on building what is essentially a national bullpen of turnaround specialists. The group has trained 400 principals for high-poverty schools since 2006, but plans to develop some 2,000 leaders over the next four years, according to Jean Desravines, the NLNS director.

Some cities are looking for inventive ways to entice existing "stars" to work in failing schools. In 2008, Peter Gorman, superintendent of the Charlotte-Mecklenburg, N.C., school district, held a competition to determine the most effective local principals. Then he offered the winners the chance to work at one of the worst schools in the district.

In exchange, the principals would get a raise, freedom from many district rules, and the ability to bring in eight people and transfer out five others. Every principal accepted his offer.

One school, Sterling Elementary, reported a 14-point jump in reading scores and a 24-point increase in math scores in the first year. Still, just two of the seven original schools targeted in the initiative have seen a significant impact on student achievement.

"He's the first superintendent I've worked under who has really cared about high-poverty schools," says Nancy Guzman, Sterling's principal.

* * *

At Phillips, the most persistent critics of the attempt to improve student learning are ... the students themselves. Many of them don't like the strict new rules – the uniforms, the dress code, the ban on gum, the restrictions on cellphone use.

"You can't be your own individual without your own clothes," complains Keyairra Lyda, wearing the powder-blue shirt that shows she's a sophomore.

"Some of this stuff is from grammar school," says Bruce Montgomery, a junior who particularly hates tucking his shirt in – right before he gets sent to the dean for being in the auditorium when he's supposed to be in class.

As far as Little is concerned, the students can complain all they want. "What they say and what they do are two different things," he says. "They can be upset, but when I see them acting differently, that's the most important part."

In the first two months of the school year, suspensions were way up, as students adjusted to a new zero-tolerance policy for such things as fighting and to the elimination of in-school suspensions (in which students were sent to a room as a disciplinary measure instead of being expelled, as they are now). But at 20 weeks into the school calendar, there were 135 suspensions, compared with 217 last year.

Students – and their parents – also complain heavily about the new grading scale, which they say is too hard. "I used to be an AP student on the honor roll, and now I've got an F," says Tyrice McClaren, who is eating an unappetizing looking chicken sandwich from the cafeteria.

But Little says when he saw students with a 3.7 GPA scoring 14 on the ACT (an abysmal score on the college entrance exam's 36-point scale), he knew that grades had little correlation with what students were learning. And while some students are vocal in their complaints, a number of others say they really do see a big difference – and are learning a lot more.

"It's too strict, but I like the education," says Ronald Kyle, a junior who's started playing the snare drum in the band. "If you don't understand, you ask the teachers a question. Last year, if you missed it, they wouldn't go over it again."

His friend Tyree Valentine, who says he was so angry initially that he wanted to transfer, agrees. "I'm learning," he says.

* * *

Between 1997 and 2009, Markham Middle School in Los Angeles went through a series of targeted efforts designed to turn around the school, first initiated by the State of California and later through the federal No Child Left Behind Act.

It changed curricula and teaching formats, hired new principals and teachers. Yet in 2009, at the end of all the reforms, just 3 percent of the students scored at the proficient level in math, and 11 percent in English.

"Changing that long-run history is really hard," says Robert Manwaring, a consultant who last year wrote a study on turnarounds that highlighted Markham for the think tank Education Sector .

Countless other examples exist across the country – evidence to critics that chronically poor schools rarely improve. While unions and others on the left attack the turnaround movement for laying off teachers and ignoring broader factors in poor achievement, like poverty, some on the right simply see it as throwing money after a lost cause.

Last year, a study by the Washington, D.C.-based Thomas B. Fordham Institute found that, of 2,000 bottom-tier schools it examined in 10 states over five years, only about 1 percent truly turned around (defined by the study as climbing from the bottom 10 percent to above the state's average). A few more schools – less than 10 percent – achieved modest improvement.

"The thinking is that we have to do something, so we'll throw some money and more requirements [at the schools] and see what happens, but I don't think we should be optimistic," says Michael Petrilli, vice president for national programs and policy at Fordham. "If we're honest, we'll say that nobody knows how to turn low-performing schools into high-performing schools [at a systematic level], and there is little reason to believe that this latest federal effort will change that equation."

The most typical answer to that argument is: OK, then what do we do? Just give up on failing schools and the students who attend them? Close them down? Closing schools isn't an option in many districts because no better ones exist for students to attend. Another possible solution – dispersing high-poverty, high-minority populations across the district – isn't easy either. While there's evidence it can help students academically, busing is a political and logistical nightmare.

"We're choosing between a bunch of bad options," acknowledges Mr. Petrilli.

Some argue the problem isn't that there aren't remedies for bad schools. It's that the remedies most people try aren't dramatic enough. "Many of these schools have really been focused on marginal change," says Mr. Manwaring. "As a result, they've gotten marginal changes in outcomes, if any."

To improve the chances of a turnaround, Mass Insight Education, a nonprofit group in Boston, says its research suggests several elements are important: picking the right moment to take over a school; making teachers and others connected with it reapply for their jobs; and freeing the staff from collective-bargaining agreements and restrictions on hiring, firing, and curriculum.

While those may be unpopular moves in some quarters, Justin Cohen, head of Mass Insight's School Turnaround Group, believes wholesale change offers the best chance of success. His biggest worry about the new federal push is that too many of the attempted turnarounds will fail – due in part to what he calls "light-touch" reforms.

Nor can schools be fixed by simply plugging in some magic formula. What works in one location doesn't necessarily translate to another. Experts say people are the key to success and that includes more than good administrators and teachers: It also means organizational support from the district or an outside group like AUSL.

Yet the benefits of doing it right can be huge. "I don't think there's any more powerful story for the potential of education change than school turnarounds," says Mr. Cohen.

* * *

Last fall at Phillips, Little was struggling with how to deal with a junior named Dimples. For the first two months, he estimates, she might have been in school four days. She'd come, curse at everyone, get sent home for a 10-day suspension, and then repeat the process all over again.

In November, he noticed she'd been in school for two straight weeks and called her in to talk, wondering what had happened. Dimples said she was starting a petition because she didn't like the way the school was being run under the new rules.

"Great!" he told her, finding her plan infinitely more productive than the earlier behavior. A few days later, when he asked how the petition was going, Dimples said she had thrown it away. After being in school for a few weeks, she decided she liked it. She hasn't been suspended since. She has participated in extracurricular activities for the first time and is now one of the school's best bowlers.

For Little, Dimples illustrates the struggles, but also the signs of success. "All it took was to get her engaged," he says. "She lost all that instructional time during the first two months of school, but now we've got her rolling, and she's running."

Phillips is about six months into its first year as a turnaround school – too soon to pronounce it a success or failure. But at least some signs are encouraging. In a variety of classes, students all appear attentive and engaged, no matter how much they may struggle with the lesson material. Few disruptions break out in the hallways between classes.

Attendance is up 15 percentage points from last year (though at 69 percent, it could certainly improve more). Students – drawn in by the freshmen, who now have to take part in after-school activities like band or sports for their physical education credit – are starting to participate again. The band played in three city parades this year, and Phillips fielded a debate team for the first time in a decade.

The results of the big annual tests and ACTs, which take place this month, won't be known for some time. But students seem to be learning. They took an exam at the beginning of the year and then again four months later, at Christmas, and, according to Little, had made nine months' progress.

The principal's tough new grading system, in which anything below 75 is an F, points to improvements, too. After the first five weeks, teachers had handed out a failing grade to all but 31 of the 650 students in the school. By the 20-week mark, 196 were without an F.

"We've affected a third of our population," says Little. "The goal is to get to two-thirds by the end of the year."

If the indefatigable Little and the teachers at Phillips can succeed, especially with a high school, they'll be defying academic gravity. Even the most optimistic turnaround advocates suggest that if all goes well with this latest federal initiative, a fraction of the schools might actually achieve their goal.

"It's the right mission for the country, both educationally and morally," says Timothy Knowles, director of the University of Chicago's Urban Education Institute, who believes a 30 percent success rate would be a remarkable achievement. "But we need to temper our exuberance."