A federal program that provides housing vouchers to help poor families move out of high-poverty neighborhoods appears to be having little impact so far on children's academic achievement, a new report finds. Four to seven years after leaving their old neighborhoods, the study found, children who took part in the program were doing no better in school than their peers who stayed behind in public-housing projects. The study, which was posted January 2006 on the Web site of the National Bureau of Economic Research, follows up on 2,300 families who took part in the federal Moving to Opportunity for Fair Housing program in the 1990s. Championed by politicians on both the right and the left, the program is an ambitious, 10-year experiment by the U.S. Department of Housing and Urban and Development to determine what would happen if poor families were given the means to raise their children in better neighborhoods. It has provided housing vouchers to disadvantaged families from five cities--Baltimore, Boston, Chicago, Los Angeles, and New York--in the hope that they would use them to migrate to safer, more prosperous neighborhoods with better schools and job prospects. Yet while the program is reducing some of the psychological and physical stresses that families experience, the researchers found, it has so far failed to produce educational gains for their children, regardless of how young those children were when their families left public housing.