The well-being of teenagers has improved slightly since 2000, but, for babies, it's much worse, according to a national study evaluating the lives of children.

The most dramatic change is the 8 percent increase between the years 2000 and 2005 of newborns weighing less than 5 1/2 pounds, said Laura Beavers, coordinator of 2008 KIDS COUNT, a 196-page national study of children age 19 and younger, released today by the Annie E. Casey Foundation.

In 2005, the number of babies with low birth weight nationally was the highest in 40 years for seven racial and ethnic groups, said Beavers. The highest rate was for white, non-Hispanic babies compared with other racial categories.

By comparison, the number of Pennsylvania's newborns with low weight increased by 9 percent, higher than the national average.

Out of 50 states, Pennsylvania ranked 23rd in caring for the overall well-being of its children ages 19 and younger, the study found.

Between 2000 and 2006, Pennsylvania showed three positive trends: fewer teen pregnancies, fewer child deaths between ages 1 and 14, and a reduction in the school dropout rate (along with 43 other states).

One area remained the same in the Keystone State: the number of teens not attending school or working.

Besides low birth weight, five other trends also worsened in the state: infant mortality rate; teen death rate; children in families where no parent had a full-time year-round job; children living in poverty, and children in single-parent families.

Nationally, the teen-death rate and the rate of teens not in school and not working was lower than in Pennsylvania.

In Pennsylvania in 2006, 2.8 million children were under age 18, including 1.34 million youngsters between 10 and 17 years old.

In the 10-to-15 age group, 77 percent were white, 13 percent were black, 6 percent were Hispanic, 2 percent were Asian or Pacific Islander, 2 percent more than one race and fewer than 0.5 percent were American Indian or Alaskan native.

Nine percent of the children came from immigrant families, compared with 22 percent nationally.

* EDUCATION: Pennsylvania students did slightly better than the national average in math and reading in fourth and eighth grades - even though scores were low.

In fourth grade, only 40 percent of the state's students scored at or above a proficient reading level, compared with 32 percent nationally. Math scores were 47 percent at or above proficiency, compared with 39 percent nationally.

By the time the state's students reached eighth grade, however, reading-proficiency levels dipped to 36 percent, with 38 percent in math, compared with the national average of 29 percent in reading and 31 percent in math.

* HEALTH: In Pennsylvania, 228,000 children, or 8 percent, have no health insurance, compared with 8.1 million children, or 11 percent, nationally.

Of those without health care, 15 percent of the children have special health-care needs, compared with 14 percent nationally.

* INCOME: In 2006, Pennsylvania families with children earned a median income of $57,400 - $3,000 more than the national average. The poverty level was $20,444 for a family of two adults and two children.

However, the number of children living in extreme poverty (50 percent below the poverty line) was the same 8 percent in the state and the U.S.