Who

A nationally representative sample of 14,000 children born in the year 2001. The children participating in the study came from diverse socioeconomic and racial/ethnic backgrounds with oversamples of Asian and Pacific Islander children, American Indian and Alaska Native children, Chinese children, twins, and low and very low birth weight children.

When

The ECLS-B is a longitudinal study. The same children have been followed from birth through kindergarten entry. Information about these children was collected when they were approximately 9 months old (2001-02), 2 years old (2003-04), 4 years old/preschool age (i.e., one year away from kindergarten, 2005-06). Additionally, in the fall of 2006, data were collected from all participating sample children, approximately 75 percent of whom were in kindergarten or higher. In the fall of 2007, data were collected from the remaining 25 percent of participating sample children who had not yet entered kindergarten or higher in the previous collection, as well as children who were repeating kindergarten in the 2007-08 school year.

What

Children, their parents, their child care providers, and their teachers provided information on children's cognitive, social, emotional, and physical development across multiple settings (e.g., home, child care, school). Additionally, information on children's elementary schools is available by linking the ECLS-B data to school data from NCES's Common Core of Data (CCD) and Private School Survey (PSS) universe files, which pertain to U.S. public and private schools, respectively.

Where

Information was collected from children, their families, their child care providers, and their teachers all across the United States.

How

At all waves (9 months, 2 years, preschool, and the two kindergarten collections), parent respondents (who were usually the child's mother) were asked about themselves, their families, and their children; fathers were asked about themselves and their role in their children's lives; and children were observed and participated in assessment activities. In addition, beginning when the children were 2 years old, their child care and early education providers were asked to provide information about their own experience and training and their setting's learning environment. At 2 years and preschool, a subssample of children in regular nonparental care and education had their care settings observed to obtain information on the quality of the setting. When the ECLS-B children were in kindergarten, their teachers were asked to provide information about children's early learning and the school and classroom environments.