A third of the way into the decade, Washington had fewer school-age children but more toddlers than in 2000, a higher proportion of homeowners and sharply increased housing values, according to census figures released yesterday that document a rapidly changing city.

The numbers, which come from a monthly household survey, offer an intriguing but sometimes contradictory portrait of social change from 2000 to 2003. For example, there are both more married couples and more single mothers in the District.

The Census Bureau also released national rankings of 233 big counties, also based on the American Community Survey, that underscored the region's image as relatively prosperous and crowded. Local counties were at the top in income, educational achievement and commuting times.

Average household incomes in Howard, Prince William, Fairfax and Montgomery counties -- all at least $73,000 -- were among the nation's highest, reflecting the region's skilled workforce and its high cost of living. Fairfax, Montgomery and Howard, where at least half of residents have college degrees, also are among the nation's best-educated communities.

Prince William County and Prince George's County hold a more dubious distinction, according to the survey: They had among the nation's longest average commutes, more than 34 minutes each.

Previous census figures showed Washington's population declining slightly but at nowhere near the rate of recent decades. The latest numbers fill in details of how the District's demographics changed from 2000 to 2003 because of immigration, gentrification, economic development and other forces.

Overall, the city has fewer school-age children than it did in 2000, but the under-5 population has gone up slightly, the figures show.

"I can bear witness to that right in my own neighborhood," said Deborah Redmond, an advisory neighborhood commissioner from Barnaby Woods in Northwest Washington. "I get a lot of calls from constituents who have young children who want sidewalks and want the cars to slow down."

For years, the poor quality of the city's public schools has pushed parents to the suburbs as their children reach school age. Redmond said that trend could continue unless city officials act quickly, because the parents of young children who she knows already are concerned.

"I hear from them that they would love to send them to the public schools," she said, "but every single one of them tells me that in the next few years they are going to have to make a decision."

In Crestwood, an affluent black neighborhood in Northwest, there are so few children that residents have had to import them from other parts of the city for the annual Halloween party. But James Jones, president of the Crestwood Neighborhood League, said more children now come to the yearly event, a growing number of whom are white.

"It's good to see families and little kids walking the streets," he said. "It's kind of strange to be here and not see any kid activity."

The racial change that Jones sees in Crestwood is part of a broader trend affecting the city's overall mix. The city's majority-black population, which has been shrinking for decades, continues to decline. The census survey said blacks accounted for 59 percent of the household population in 2003, compared with 61 percent three years earlier. During that same period, the city's white, Asian and Latino population shares rose.

The District, though not an immigration hub like some other big cities, is gaining foreign-born residents, according to the new survey. It found that immigrants made up 15 percent of the District's household population in 2003, about half of the percentage in Fairfax and Montgomery counties. Half the city's immigrants are from Latin America.

The new survey also points to a continuing rise in homeownership in the city in the past three years, partly attributable to construction downtown and east of the Anacostia River. City officials encourage homeownership, because owners tend to be more stable and well-off than renters, but some activists are concerned that gentrification is pushing poorer renters out of the city.

Robert Lang, director of the Metropolitan Institute at Virginia Tech, said the city's homeownership rate grew at a faster rate than the nation's. He attributes that fact to a mix of low interest rates, a first-time buyer tax credit and the city's support of housing construction.

"This is the kind of indicator that is more important than the gross figure on population," he said. "This is what I would consider a greater measure of health."

The survey shows that the city's home values have zoomed this decade -- from a median value of $177,619 in 2000 to $248,171 last year. A median value means that half the houses were worth less, and half were worth more.

"I hear a number of complaints. We're all concerned that the prices are shooting up so fast," said Gregory New, a past president of the D.C. Federation of Civic Associations. "We like the fact that our houses are going up, but we don't like the taxes."

The American Community Survey, derived from an annual sample of 800,000 households, includes counties with more than 250,000 people. It does not include people living in group quarters such as college dormitories, prisons and nursing homes. Its methodology is different from the Current Population Survey, which was the basis for income and poverty figures released yesterday by the Census Bureau.