The National Center for Education Statistics has released preliminary findings from the Early Childhood Longitudinal Study, providing the first look at the demographic data on the students enrolled in U.S. kindergartens during the 2010-11 academic year. The report contains information on kids attending both private and public kindergarten, those enrolled full- and part-time, and children attending the program for the first time as well as those enrolling for the second year.

The ECLS-K:2011 is a longitudinal study that will follow a nationally representative sample of students from their kindergarten year to the spring of 2016, when most of them are expected to be in fifth grade. During the first year of data collection, when all children were in kindergarten, data were collected in both the fall and the spring. Approximately 18,200 children enrolled in 970 schools during the 2010-11 school year participated during the kindergarten year.

Nearly 3.5 million students in the country entered kindergarten for the first time in 2010, and most of them were born before September of 2005. Only 7% of those enrolled in a kindergarten program were younger than five when they first started attending. More than half of the kindergarteners surveyed where white, while a quarter were of categorized as Hispanic. Asians made up 4% of the incoming class, with black students making up about 13% of the total.

On the whole, students who began kindergarten later tended to have better literacy and math skills prior to enrolling. Those born between January of 2004 and August 2004 scored the best on mathematics assessment test, and had second-best scores on the reading assessment tests. Children born between September 2004 and December 2004 topped the list in literacy.

In addition, the two groups of first-time kindergartners born from September 2004 through April 2005 (those born September-December 2004, and those born January-April 2005) both scored higher in reading and math than did kindergartners in any of the three groups born in May 2005 or later (those born May-August 2005, those born September-December 2005, and those born after December 2005).

Of all ethnic and racial groups, Asian students had the highest scores in reading and mathematics, followed closely by white students. Although they scored lower than their Asian and white peers, black kids fared better than their Hispanic and American Indian/Alaska Native classmates.

Scores also varied greatly by income with the best results obtained by children from higher-income families. Students from families with incomes below the federal poverty level scored the worst on all assessment exams.