Research: Controlling for social class and children's books in the home
More evidence of the importance of libraries and books in children's lives.
Controlling for social class and children's books in the home closes
the black-white in kindergarten: An important result buried deep in
Fryer and Levitt (2004)
by Stephen Krashen
Fryer and Levitt (2004) examined reading and math test scores in
kindergarten and grade 1 using data from the Early Childhood
Longitudinal Study (about 1000 schools). Their focus was the gap
between black and white children.
For reading, the difference between black and white children at the
start of kindergarten was .40 (where 0 = mean, sd = 1). Thus, black
children scored 40% of one standard deviation below white children.
When Fryer and Levitt controlled for SES, (parents education, parent
occupation, household income), the gap dropped to .134.
When they controlled for SES and number of children's books in the
home the gap dropped to nearly zero, -.006.
This is a major result: social class and the presence of children's
books evens the playing field. And this is only for a test given at
the start of kindergarten. As they note, "including number of books
…. completely eliminates the gap in reading" (p. 452).
As is typical for these kinds of results, it is buried deep in this
When Fryer and Levitt controlled for more predictors, including age at
kindergarten, birth weight, whether the mother was a teenager or age
30 at the time her first child was born, the characteristics of
neighborhood, whether mother was working, preschool program
participation, parental involvement in child's life, family size and
family structure, the difference was.093. Black children did slightly
Fryer and Levitt did not find the same "summer slump" than others have
reported: In fact, black children closed the gap slightly over the
summer. But the summer in this study was between kindergarten and
grade 1. Closing the summer gap is related to access to books and
self-selected reading over the summer (studies by Heyns, 1975 and by
J. Kim, 2003). Not much self-selected reading takes place with six
As usual, there was no mention of libraries of any kind.
Fryer, R. and Levitt, S. 2004. Understanding the black-white test
score gap in the first two years of school. The Review of Economics
and Statistics 86 (2): 447-464.
Heyns, B. 1975. Summer Learning and the Effect of School. New York:
Kim, J. 2003. Summer reading and the ethnic achievement gap. Journal
of Education for Students Placed at Risk 9(2): 169-188
INDEX OF RESEARCH THAT COUNTS