But on a good day, only six of the school's 14 computers worked. He never knew which ones until he sat down and searched for a flicker of life on the screen. "It was like Russian roulette," says Rhodes, a tall young man with an older man's steady gaze. If he picked the wrong computer, the teacher would give him a handout. He would spend the rest of the period learning to use Microsoft Word with a pencil and paper.

One day last fall, tired of this absurdity, Rhodes e-mailed Michelle Rhee, the new, bold-talking chancellor running the District of Columbia Public Schools system. His teacher had given him the address, which was on the chancellor's home page. He was nervous when he hit SEND, but the words were reasonable. "Computers are slowly becoming something that we use every day," he wrote. "And learning how to use them is a major factor in our lives. So I'm just bringing this to your attention." He didn't expect to hear back. Rhee answered the same day. It was the beginning of an unusual relationship.

The U.S. spends more per pupil on elementary and high school education than most developed nations. Yet it is behind most of them in the math and science abilities of its children. Young Americans today are less likely than their parents were to finish high school. This is an issue that is warping the nation's economy and security, and the causes are not as mysterious as they seem. The biggest problem with U.S. public schools is ineffective teaching, according to decades of research. And Washington, which spends more money per pupil than the vast majority of large districts, is the problem writ extreme, a laboratory that failure made.

Rhee took over Anacostia High and the district's 143 other schools in June 2007, when Mayor Adrian Fenty named her chancellor. Her appointment stunned the city. Rhee, then 37, had no experience running a school, let alone a district with 46,000 students that ranks last in math among 11 urban school systems. When Fenty called her, she was running a nonprofit called the New Teacher Project, which helps schools recruit good teachers. Most problematic of all, Rhee is not from Washington. She is from Ohio, and she is Korean American in a majority-African-American city. "I was," she says now, "the worst pick on the face of the earth."

But Rhee came highly recommended by another prominent school reformer: Joel Klein, chancellor of New York City's schools. And Rhee was once a teacher ― in a Baltimore elementary school with Teach for America ― and the experience convinced her that good teachers could alter the lives of kids like Rhodes.

Anacostia High has a 24% graduation rate, and only 21% of its students read at grade level. Rhodes is well aware of the miserable statistics, and when he first saw his new chancellor from afar, he thought she looked petite, foreign and under qualified. "I was like, She doesn't look ready for urban kids." But after they exchanged e-mails, he agreed to meet her downtown. He realized almost at once that he had underestimated her. "She actually sat with me," he says, "and talked eye to eye, like I was one of her co-workers." They decided to meet again, this time at Anacostia High. Rhodes began to talk about Rhee to his classmates, and they started writing an agenda for the meeting, detailing all the things that were wrong with the D.C. school system. They had much to tell.

Rhee has promised to make Washington the highest-performing urban school district in the nation, a prospect that, if realized, could transform the way schools across the country are run. She is attempting to do this through a relentless focus on finding ― and rewarding ― strong teachers, purging incompetent ones and weakening the tenure system that keeps bad teachers in the classroom. This fall, Rhee was asked to meet with both presidential campaigns to discuss school reform. In the last debate, each candidate tried to claim her as his own, with Barack Obama calling her a "wonderful new superintendent."

Hard as it is to imagine Washington schools ranking among the best in the country, the city does have some things working in its favor. The system is relatively small, making it easier to redirect. As in New York City, the board of education was recently dissolved, which means changes can be made without waiting for the blessing of a fractious body of overseers. And now that a third of Washington's kids are in charter schools, there is intense pressure on the public system to keep the students it still has. If they keep fleeing the system at the current rate, enrollment will drop 50% every 10 years.

Each week, Rhee gets e-mails from superintendents in other cities. They understand that if she succeeds, Rhee could do something no one has done before: she could prove that low-income urban kids can catch up with kids in the suburbs. The radicalism of this idea cannot be overstated. Now, without proof that cities can revolutionize their worst schools, there is always a fine excuse. Superintendents, parents and teachers in urban school districts lament systemic problems they cannot control: poverty, hunger, violence and negligent parents. They bicker over small improvements such as class size and curriculum, like diplomats touring a refugee camp and talking about the need for nicer curtains. To the extent they intervene at all, politicians respond by either throwing more money at the problem (if they're on the left) or making it easier for some parents to send their kids to private schools (if they're on the right).

Meanwhile, millions of students left behind in confused classrooms spend another day learning nothing.

A Teacher from Toledo

One day in August, I spent the morning with Rhee as she made surprise visits to Washington public schools. She emerged from her chauffeured black SUV with two BlackBerrys and a cell phone and began walking ― fast ― toward the front door of the first school. She wore a black pencil skirt, a delicate cream blouse and strappy high heels. When we got inside, she walked into the first classroom she could find and stood to the side, frowning like a specter. When a teacher stopped lecturing to greet her, she motioned for the teacher to continue. Rhee smiled only when students smiled at her first. Within two minutes, she had seen enough, and she stalked out to the next classroom.

In the hallway, she muttered about teachers who spend too much time cutting out elaborate bulletin-board decorations or chitchatting at "morning meetings" with their third-graders before the real work begins. "We're in Washington, D.C., in the nation's capital," she said later. "And yet the children of this city receive an education that every single citizen in this country should be embarrassed by."

In the year and a half she's been on the job, Rhee has made more changes than most school leaders ― even reform-minded ones ― make in five years. She has shut 21 schools ― 15% of the city's total ― and fired more than 100 workers from the district's famously bloated 900-person central bureaucracy. She has dismissed 270 teachers. And last spring she removed 36 principals, including the head of the elementary school her two daughters attend in an affluent northwest-D.C. neighborhood.

Rhee is convinced that the answer to the U.S.'s education catastrophe is talent, in the form of outstanding teachers and principals. She wants to make Washington teachers the highest paid in the country, and in exchange she wants to get rid of the weakest teachers. Where she and the teachers' union disagree most is on her ability to measure the quality of teachers. Like about half the states, Washington is now tracking whether students' test scores improve over time under a given teacher. Rhee wants to use that data to decide who gets paid more ― and, in combination with classroom evaluation, who keeps the job. But many teachers do not trust her to do this fairly, and the union bristles at the idea of giving up tenure, the exceptional job security that teachers enjoy.

Rhee grew up in a nice neighborhood in Toledo, Ohio, a middle child, between two brothers. Her parents immigrated from South Korea several years before she was born so that her father could study medicine at the University of Michigan. He became a specialist in rehabilitation and pain medicine, and her mother owned a women's clothing store. Education was highly valued in the family, as was independence. After Rhee finished sixth grade, her parents sent her to South Korea to live with an aunt and attend a Korean school, a harrowing experience for a child in a strange land with limited skills in its language. When she returned a year later, her parents sent her to a private school because they found the public schools lacking.

After Rhee graduated from Cornell University in 1992, she joined Teach for America. She spent three years teaching at Harlem Park Elementary, one of the lowest-performing schools in Baltimore. Her parents visited and were stunned by the conditions of the neighborhood. "The area where the kids lived reminded me of a scene after the Korean War," says her father Shang Rhee.

Rhee suffered during that first year, and so did her students. She could not control the class. Her father remembers her returning home to visit and telling him she didn't want to go back. She had hives on her face from the stress.

The second year, Rhee got better. She and another teacher started out with second-graders who were scoring in the bottom percentile on standardized tests. They held on to those kids for two years, and by the end of third grade, the majority were at or above grade level, she says. (Baltimore does not have good test data going back that far, a problem that plagues many districts, so this assertion cannot be checked. But Rhee's principal at the time has confirmed the claim.) The experience gave Rhee faith in the power of good teaching. Yet what happened afterward broke her heart. "What was most disappointing was to watch these kids go off into the fourth grade and just lose everything," Rhee says, "because they were in classrooms with teachers who weren't engaging them."

The summer after her second year of teaching, Rhee met Kevin Huffman, a fellow Teach for America member. They married two years later and had two daughters, Starr and Olivia, now 9 and 6. They moved to Colorado to be closer to Rhee's parents, but the marriage faltered. Huffman and Rhee separated, agreeing to joint custody of the kids. And then Rhee got the offer to run Washington's schools. Huffman, now head of public affairs for Teach for America, had no illusions about the challenges Rhee would face. But when he heard about the job offer, he decided to follow her to D.C. "Even though moving didn't sound like a whole lot of fun," he says, "the reality is that I genuinely believed that she had the potential to be the best superintendent in the country. Most people think about their own longevity, about political considerations." He adds, "Very few people genuinely don't care about anything other than the end result for kids. Michelle will compromise with no one when it comes to making sure kids get what they deserve."

Scorched Earth

When they arrived in Washington, Huffman and Rhee anted up. They enrolled Starr and Olivia in Oyster-Adams, a public elementary school. Although the school is considered among the best in the city, Rhee quickly concluded that it was inferior to the Colorado public school her daughters had been attending. Among other things, the homework was sporadic and unchallenging, she says. Rhee dismissed the principal before the school year was out, a move that sparked outrage across the city and in her own home. "That," she says, "was probably the decision I got the most grief about."

Rhee is, as a rule, far nicer to students than to most adults. In many private encounters with officials, bureaucrats and even fundraisers ― who have committed millions of dollars to help her reform the schools ― she doesn't smile or nod or do any of the things most people do to put others at ease. She reads her BlackBerry when people talk to her. I have seen her walk out of small meetings held for her benefit without a word of explanation. She says things most superintendents would not. "The thing that kills me about education is that it's so touchy-feely," she tells me one afternoon in her office. Then she raises her chin and does what I come to recognize as her standard imitation of people she doesn't respect. Sometimes she uses this voice to imitate teachers; other times, politicians or parents. Never students. "People say, 'Well, you know, test scores don't take into account creativity and the love of learning,'" she says with a drippy, grating voice, lowering her eyelids halfway. Then she snaps back to herself. "I'm like, 'You know what? I don't give a crap.' Don't get me wrong. Creativity is good and whatever. But if the children don't know how to read, I don't care how creative you are. You're not doing your job."

Rhee's ferocity has alienated many people ― even those who support her ideas and could be helpful to her. This summer the chair of the Washington city council called dealing with Rhee a "nightmare." There has been talk of passing legislation to rein her in. "Michelle Rhee believes in scorched earth," says Randi Weingarten, president of the American Federation of Teachers, a national union that has become unusually involved in local matters in Washington. "I am not saying that D.C.'s school system doesn't need a lot of help. But I have been part of a lot of reforms, and the one thing I have never seen work is a hierarchical, top-down model."

Rhee is aware of the criticism, but she suggests that a certain ruthlessness is required. "Have I rubbed some people the wrong way? Definitely. If I changed my style, I might make people a little more comfortable," she says. "But I think there's real danger in acting in a way that makes adults feel better. Because where does that stop?"

The Data

On Rhee's tour of schools during the first week of classes this year, a parent stopped her to praise her accomplishments so far. Rhee listened with a small smile while systematically cracking each of her knuckles with the thumb of the same hand. Then she got back into her SUV and began furiously e-mailing. When she calls her staff, she does not say hello; she just starts talking. She answered 95,000 e-mails last year, according to her office.

She frequently sounds exasperated. "People come to me all the time and say, 'Why did you fire this person?'" she says. The whiny voice is back. "'She's a good person. She's a nice person.' I'm like, 'O.K., go tell her to work at the post office.' Just because you're a nice person and you mean well does not mean you have a right to a job in this district."

The data back up Rhee's obsession with teaching. If two average 8-year-olds are assigned to different teachers, one who is strong and one who is weak, the children's lives can diverge in just a few years, according to research pioneered by Eric Hanushek at Stanford. The child with the effective teacher, the kind who ranks among the top 15% of all teachers, will be scoring well above grade level on standardized tests by the time she is 11. The other child will be a year and a half below grade level ― and by then it will take a teacher who works with the child after school and on weekends to undo the compounded damage. In other words, the child will probably never catch up.

The ability to improve test scores is clearly not the only sign of a good teacher. But it is a relatively objective measure in an industry with precious few. And in schools where kids are struggling to read and subtract, it is a prerequisite for getting anything else done. In their defense, Washington teachers and principals, like educators in many of the country's worst school districts, talk about trying to teach a seventh-grader who is eight months pregnant; about being assaulted by students; about holding meetings for parents, replete with free food, and no one showing up. Washington Teachers' Union leader George Parker worries that test-score data cannot take all this into account: "I don't think our teachers are afraid of demonstrating student growth, but you have to look at the dynamics of the children you're dealing with. If I'm teaching children who have computers at home, who have educated parents, those students can move a lot faster than kids whose parents can't read."

Rhee says she does not expect all kids to move up the charts at the same rate; the important thing is to demand that most do move up. "This is a cultural shift," says Kaya Henderson, Rhee's deputy. "For years, there were no data, and you were a good teacher because the parents or your principal told you so. And so this is a scary thing."

The most glaring example of the backward logic of schools is the way most teachers receive lifetime job security after one or two years of work. As Larry Rosenstock, CEO of eight California charter schools, noted at an education panel last spring, we don't give that kind of job security to pilots or doctors ― or any others who hold our children's fate in their hands: "What is it that is so exceptional about teachers that they should have this unique right?"

Teachers got tenure rights in the early 20th century to protect them against meddling politicians and school-board members who treated their jobs as patronage pawns. But the rationale is plainly antiquated. Today dozens of federal and state laws protect teachers and other people from arbitrary firing. But most teachers still receive tenure almost automatically. In fact, even before they get tenure, they are rarely let go. Schools spend millions of dollars evaluating teachers, but principals have little incentive to shake up their staffs, and so most teachers end up scoring near the top. "What I'm finding is that our principals are ridiculously ― like ridiculously ― conflict-averse," Rhee says. "They know someone is not so good, and they want to give him a 'Meets expectations' anyway because they don't want to deal with the person coming into the office and yelling and getting the parents riled up."

Right now, schools assess teachers before they teach ― filtering for candidates who are certified, who have a master's degree, who have other pieces of paper that do not predict good teaching. And we pay them the same regardless of their effectiveness.

By comparison, if we wanted to have truly great teachers in our schools, we would assess them after their second year of teaching, when we could identify very strong and very weak performers, according to years of research. Great teachers are in total control. They have clear expectations and rules, and they are consistent with rewards and punishments. Most of all, they are in a hurry. They never feel that there is enough time in the day. They quiz kids on their multiplication tables while they walk to lunch. And they don't give up on their worst students, even when any normal person would.

Students know this instinctively. Acquirra Carter, 14, attends Washington's Cardozo High School, where, she complains, kids walk out of classes when they get bored and certain teachers talk on their cell phones when they are supposed to be teaching. But there are exceptions, and Carter knows them when she sees them. "Some teachers find a way. Mrs. Brown, they would not dare walk out of her class. She has total control. Mrs. Lawton, nobody leaves her class. This boy whispered, and she knew it!"

Minefields in the Schoolyard

In the view of Rhee and reformers like her, the struggle to fix America's failing school system comes down to a simple question: How do you get the best teachers and principals to work in the worst schools? In her quest to figure this out, Rhee has already suffered a major setback. Earlier this year, she proposed a revolutionary new model to let teachers choose between two pay scales. They could make up to $130,000 in merit pay on the basis of their effectiveness ― in exchange for giving up tenure for one year. Or they could keep tenure and accept a smaller raise. Currently, the average teacher's salary in Washington is $65,902. The proposal divided the city's teachers into raging, blogging factions. This fall, the union declined to put Rhee's proposal to a vote, and its relationship with her has become increasingly hostile.

In October, Rhee vowed to purge incompetent teachers through any means necessary. She has brought on extra staff to help principals navigate the byzantine termination process and says an unprecedented number of teachers have already been put on notice. But she cannot give teachers the huge raises she proposed unless the union agrees to a new contract. So this approach will be slower, more litigious and less inspiring. In other words, it will be all stick and no carrot. It's hard to say if anyone else would have been able to persuade the union to trade away tenure for cash bonuses, but Rhee's sometimes dismissive attitude made it harder for some teachers to trust her.

For now, Mayor Fenty says he still has full confidence in Rhee, and he claims Washington residents share his enthusiasm. "Regular people love the fact that for once someone is making tough decisions for D.C. schools," says Fenty, who attended the district's public schools. But the disconnect between Rhee's confident, sweeping rhetoric and the tortured reality is sizable, and it is most apparent at ground level, in the schools she is trying to save.

Rhee likes to tell the story of how Rhodes got in touch with her. She recounted it on TV on The Charlie Rose Show in July: "A student sent me this e-mail and said, basically, If you really want to know what's wrong with our schools, you should come and talk to the kids because I'm afraid that by talking to the adults, you might not be getting the real story."

Rhodes has a more nuanced version of the story. After their initial meeting, they met for a second time at Anacostia High, in a room off the library. Rhodes had invited eight fellow students, and they gave Rhee their typed agenda. They talked about the need for better teachers, as Rhee emphasizes when she tells the story. But Rhodes says he also told her about the holes in the floors, the lack of supplies and the fact that most classes did not have enough books for the students to take home. Rhee listened but did not offer many specific solutions. "She was vague," Rhodes says. "I got the sense she didn't want to make promises she couldn't keep."

Then one day last May, Rhee dismissed Anacostia's principal. Rhodes was devastated. He sent Rhee a furious e-mail. "My principal is a mother, mentor and a teacher to us all," he wrote. "I refuse, NO! we refuse the students of Anacostia to let her go." Rhee wrote him back. "She told me not to worry about it," Rhodes says quietly.

One of the things that make school reform so wrenching and slow is that schools become embedded in people's hearts. This is true in rich neighborhoods and poor ones, with good schools and bad. Rhodes talks about his school as if it were an extension of himself. He talks about "my teachers" and "my staff," and he refers to other students as "my colleagues." "I love Anacostia High School," he says. At the same time, he is dismayed by his school. He walks through his halls, pointing out the litter on the floor and the broken lockers. Rhodes is 6 ft. 8 in. (2 m) tall, so he has to look down to talk to almost everyone. He wears white tube socks under his black Nike flip-flops and carries his large frame deliberately, like a gentle overseer. "You see all these lockers? None of them work," he says. "This classroom over here is supposed to be for home economics, but it's never been fixed up."

Rhodes did not contact Rhee again. This year Anacostia has a new principal, and Rhodes admits that the school is functioning better. "All the children are wearing their uniforms," he says. "No kids are in the hallways." If you come to school without your uniform on, a security guard or an assistant principal will "snatch you up and just send you home." All the computers in his Microsoft Word classroom now work.

But on Nov. 19, Rhodes had to evacuate his school when fights broke out in the hallways and three students were stabbed. And he still doesn't use the school bathrooms, which are filthy and sometimes unsafe. He waits until he returns to his grandmother's house, where he lives.