President Bush recently joked about one of his "few flaws" -- his "swagger, which in Texas is called walking." In his handling of the No Child Left Behind Act (NCLB), the centerpiece of his education agenda, Bush has shown plenty of swagger. He talks tough about testing and dismisses his critics as obstructionists who lack the stomach for hard-nosed accountability. "I hear people say, well, I can't believe you're making people measure," he told a high school audience in Harrisburg, Pa., earlier this year. "Look, I didn't like to take tests either, but that's too bad. We've got to know. "

But tests merely show where there's a problem, and sanctions merely direct people to do something immediate to fix it. When it comes to the protracted and sometimes costly work of improvement, Bush is long on demands but short on solutions. This has hurt education reform, damaging bipartisan relationships and stalling legislation affecting Head Start and other programs.

Things weren't always so. Bush made a promising start in passing NCLB. He nudged Republicans -- including private-school voucher fans -- into voting for a massive public-school reform package. Like Democrats and civil rights advocates, he placed a high priority on closing racial, ethnic and income-based achievement gaps. He sealed the deal by agreeing to channel a larger share of federal dollars into the poorest schools and to boost authorizations for Title I, the act's main program aiding disadvantaged students.

No Child Left Behind demands more of states and school districts than any previous federal education law. Every public school is held accountable for the achievement of every public school student -- even schools that don't directly benefit from federal aid and students not served by federal programs. (Private schools are not affected.) By 2006, every academic subject must be taught by a highly qualified teacher. By 2014, all students are expected to know enough to pass challenging state achievement tests. Schools must already meet yearly targets for the percentage of students passing state reading and math tests. If just one group -- say, African American, poor or disabled students -- misses, the school must develop an improvement plan and allow students to transfer to better-performing public schools. Schools that continue to miss the mark undergo increasingly stiff sanctions, ending in massive reorganization or takeover by private management or the state.

The law's basic goals are the right ones. As we know from the Center on Education Policy's NCLB study, the majority of state and local officials are trying hard to meet its demands. But the Bush approach of emphasizing sanctions over support has fueled a backlash among state leaders and educators charged with making the act succeed.

Here's what went wrong. In the first two years of implementation, the U.S. Department of Education took a knuckle-rapping approach, rigidly interpreting key requirements. Schools, for example, had to test virtually all students who spoke little English or had serious disabilities with the same tests given to other students in their grade. School districts also had to allow students to transfer to a higher-performing school even when the receiving school was filled to capacity, and the districts were encouraged to add mobile classrooms or hire more teachers to accommodate the overflow. As state and local officials gained more experience carrying out the law, they raised concerns about these and other requirements that seemed unworkable or unreasonable. Some criticized what they viewed as inflexible and overly punitive methods for determining school progress or said they lacked the funds and expertise to do everything the law envisioned.

As criticism mounted, state policymakers of both parties saw NCLB as an intrusion into state control and a drain on state budgets. Nine states, including the Republican strongholds of Utah and Virginia, took steps to block state or local funds from being used to carry out the law or to opt out of its requirements by refusing NCLB allocations. Bush's rhetoric remained tough, and in May he vowed not to back down, adding, "I don't care how much pressure they try to put on the process."

Over the past several months, however, the administration has softened its stance. The Department of Education made small exceptions to guidelines for testing students with disabilities and non-English-speakers and for hiring highly qualified teachers in rural areas. It has also allowed states to change their accountability plans and even modify policies in ways the department had once forbidden. These changes have offered some short-term relief, but do not address more complicated sources of frustration, such as NCLB's failure to give credit, except in a tiny minority of cases, to schools that do improve but not enough to reach state test score targets.

The main shortcoming with Bush's leadership is his failure to provide states and school districts with the funding and tools needed to carry out NCLB, or even acknowledge that it takes more than testing and choice to turn a school around.

The president often boasts about how much federal education funding has risen on his watch. True, Department of Education appropriations have grown 32 percent since 2001, but most of the credit belongs to Congress. Over the past three years, Congress added $10.72 billion to Bush's much smaller initial budget requests. Although Bush did request significant increases for Title I, he offset them by proposing to cut other programs, such as early childhood literacy, dropout prevention and after-school programs.

The Bush requests for Title I were also well below the amounts authorized in NCLB. The administration argues that these authorizations are a maximum, not a commitment. To the Democratic co-sponsors of NCLB, however, these authorizations represent a serious promise to greatly increase appropriations that was essential to winning their votes for the act. In their eyes, Bush reneged on his promise -- one of several administration actions that have ruptured bipartisanship on education. As a result of this rift, critical education bills for college student aid, vocational education and Head Start remain stalled.

As several states have noted, the costs of implementing NCLB go well beyond the costs of designing tests and accountability systems: An Ohio study estimated the extra costs to be nearly $1.5 billion annually; a Hawaii study gauged the added costs at $30 million per year, and that doesn't include additional funds for schools in later stages of sanctions. The administration contends that the extra costs of meeting NCLB's requirements are a state and local responsibility. But look at it this way: The federal government is demanding 100 percent accountability in elementary and secondary education, while paying just 10 percent of the bill.

Intensive interventions for struggling students or troubled schools don't come cheap. For example, the SEED public charter boarding school in the District, which has been widely praised for raising test scores, costs about $25,000 per student -- that's 21/2 times the D.C. public schools' average per pupil expenditure.

What's more, although schools in several states have made good progress in raising achievement, most are far from the 100 percent mark. In Pennsylvania, for example, public schools could meet the state's 2004 test score target in math if just 35 percent of students passed the state test. Some schools that have missed targets have enormous ground to cover. In Philadelphia's Martin Luther King High School, only 7.5 percent of students passed the math test.

Real change takes hard work, applied day after day, year after year. The greatest challenge of NCLB is to determine which specific changes will help the lowest-performing schools improve and to sustain these changes when many teachers and administrators already feel constant pressure. How do schools reach students who still can't pass a reading test after years of special assistance? What else should districts do in schools that have overhauled curriculum, workshopped teachers to exhaustion, reorganized the school day and still don't show progress? What do states or private management companies do with failing schools once they've taken them over?

Bush points to local control or school choice. But even with local control, the federal government must provide technical support and leadership if it is making demands. As for choice, several cities already have too few schools that meet the law's criteria or too few seats in these schools for the children whose parents wish to switch them. Realistically, the percentage of children who switch will remain fairly small, and choice won't fix schools for those who remain.

Bush's handling of his signature legislation has disappointed many of us who care about better public schools for all children. The law still has potential to make far-reaching changes in American education, but its momentum has been stalled. Swagger won't help schools take steady steps up the rocky trail of reform. A wise leader gives people tools and resources to help meet new challenges.

Authors' e-mail:

Jack Jennings is director of the Center on Education Policy, an independent nonprofit organization that is conducting a long-term study of the No Child Left Behind Act. Nancy Kober is a writer and consultant to the center.

The Education President: He has plenty of enthusiasm, but he hasn't secured the resources to match.