Children who attend preschool do better in kindergarten than those who stay at home with their parents or relatives, according to a national report.

The federal data, which focused on children who entered kindergarten in 2010, showed that those who had some preschool experience the year before kindergarten at a child care center or a home-based program with a non-relative did better on math and reading assessments than the 15 percent who were cared for by a relative and the 21 percent who were at home with parents.

The kindergarten study was released Friday as part of a major annual federal report on the well-being of children and families. The longitudinal study will follow the kindergartners through fifth grade to see what kind of longer-term outcomes might be tied to things like different preschool experiences.

Kindergarten is the first exposure to formal schooling for many children, said Barbara Willer, the interim executive director of the National Association for the Education of Young Children, in a C-Spannterview about the findings. ”It helps determine the trajectory of success they will have later on,” she said.

The proportion of children who attend state-supported pre-kindergarten has been on the rise over the past decade, she pointed out, though numbers dipped last year.

Here are some other findings from the kindergarten study:

*Older kids did better. Kindergartners who were more than 6-years old in the fall of kindergarten had the highest average fall reading scores, and children who were less than 5-years old in the fall of kindergarten had the lowest average reading scores.

*Girls performed better in reading. Girls scored higher than boys on the reading assessments and on measures of learning readiness. There were no significant differences between girls and boys in math and science performance.

*Parental education plays a role. Kindergartners whose parents had not completed high school had the lowest fall reading scores and kindergartners whose parents had completed some graduate education had the highest fall reading scores.

*Achievement gaps already evident at the start of school. When broken down by race, white kindergartners had higher fall reading and math scores than black and Hispanic students. Asian kindergartners had higher fall reading and math scores than any other group.