The Census bureau figures were released Thursday.

As the current crop of youngsters hits kindergarten age, school systems that would otherwise be losing students will continue to grow or remain stable. They will also need to accommodate more students who were raised in households where English was not spoken.

Michael Fix is director of studies at the Washington-based Migration Policy Institute. He said although most Hispanic children younger than 5 are native-born U.S. citizens and eligible for government health care and other benefits, research shows that if their parents are not U.S. citizens, they will be less likely to get such assistance.

"All of this really reinforces the importance for counties to increase their investment in early childhood development now," Fix said. "If you don't make that investment, one of the penalties you pay down the line is that you have kids in school who don't speak English well and whose overall performance lags behind."

Demographers warned that the ethnic and socio-economic diversity of area minorities makes it difficult to make broad predictions about the effect of the area's impending shift to majority-minority status.

In Prince George's County, 62 percent of children younger than 5 are non-Hispanic blacks, and they include a substantial share born to affluent families. In Fairfax County, Asian children account for 17 percent of those younger than 5.

And Hispanic immigrants, who hail from a wide range of nations, cannot be easily categorized.

"You cannot necessarily predict that just because they'll become majority-minority, all these schools will become low-income," Fix said. "The Washington area has one of the most diverse foreign populations in the nation."