On October 5, 2006 President Bush and his secretary of education, Margaret Spellings visited Friendship-Woodridge Elementary and Middle Campus, a charter public school in Washington.  The president went to Woodridge to talk about the most ambitious piece of domestic legislation his administration had enacted after almost six years in office: No Child Left Behind. The controversial education law, which established a series of standards for schools and states to meet and a variety of penalties for falling short, is up for reauthorization next year in front of a potentially hostile Congress, and for the law to win approval again, the White House will have to convince Americans that it is working -'" and also convince them of exactly what, in this case, "working" really means.

To many people, the pledge to eliminate in just 12 years, the achievement gap between black and white students, and the one between poor and middle-class students was slowly taking effect.  It was a startling commitment, and it made the promise in the law's title a literal one: the federal government would not allow a single American child to be educated to less than that high standard.  In the first few years of this decade, two parallel debates about the achievement gap have emerged. The first is about causes; the second is about cures.  The first has been taking place in academia, among economists and anthropologists and sociologists who are trying to figure out exactly where the gap comes from, why it exists and why it persists. The second is happening among and around a loose coalition of schools, all of them quite new, all established with the goal of wiping out the achievement gap altogether.

Researchers began peering deep into American homes, studying up close the interactions between parents and children.  The first scholars to emerge with a specific culprit in hand were Betty Hart and Todd R. Risley, child psychologists at the University of Kansas, who in 1995 published the results of an intensive research project on language acquisition.  Hart and Risley showed that language exposure in early childhood correlated strongly with I.Q. and academic success later on in a child's life. Hearing fewer words, and a lot of prohibitions and discouragements, had a negative effect on I.Q.; hearing lots of words, and more affirmations and complex sentences, had a positive effect on I.Q. The professional parents were giving their children an advantage with every word they spoke, and the advantage just kept building up.

In the years since Hart and Risley published their findings, social scientists have examined other elements of the parent-child relationship, and while their methods have varied, their conclusions all point to big class differences in children's intellectual growth. Jeanne Brooks-Gunn, a professor at Teachers College, has overseen hundreds of interviews of parents and collected thousands of hours of videotape of parents and children, and she and her research team have graded each one on a variety of scales. Their conclusion: Children from more well-off homes tend to experience parental attitudes that are more sensitive, more encouraging, less intrusive and less detached -'" all of which, they found, serves to increase I.Q. and school-readiness. They analyzed the data to see if there was something else going on in middle-class homes that could account for the advantage but found that while wealth does matter, child-rearing style matters more.

The most influential schools are the ones run by KIPP, or the Knowledge Is Power Program. KIPP's founders are David Levin and Michael Feinberg.  Levin moved to New York and started the second KIPP school, in the South Bronx. As the KIPP schools grew, Levin and Feinberg adhered to a few basic principles: their mission was to educate low-income and minority students. They would emphasize measurable results. And they would promise to do whatever it took to help their students succeed.  The methods raised students' test scores, and the schools began to attract the attention of the media and of philanthropists. 

The most persistent critic of KIPP's record has been Richard Rothstein, a former education columnist for The New York Times who is now a lecturer at Teachers College. He has asserted that KIPP's model cannot be replicated on a wide scale and argues that the elevated incoming scores at the Bronx school make it mostly irrelevant to the national debate over the achievement gap. Although Rothstein acknowledges that KIPP's students are chosen by lottery, he contends in his book "Class and Schools" that they are "not typical lower-class students." The very fact that their parents would bother to enroll them in the lottery sets them apart from other inner-city children, he says, adding that there is "no evidence" that KIPP's strategy "would be as successful for students whose parents are not motivated to choose such a school."

Although the failure of No Child Left Behind now seems more likely than not, it is not too late for it to succeed. We know now, in a way that we did not when the law was passed, what it would take to make it work. And if the law does, in the end, fail -'" if in 2014 only 20 or 30 or 40 percent of the country's poor and minority students are proficient, then we will need to accept that its failure was not an accident and was not inevitable, but was the outcome we chose.

This article appeared in the November 26, 2006 edition of the New York Times Magazine.

Published Friday, Dec. 15, 2006