Parental networks, social closure, and mathematics learning: A test of Coleman's social capital explanation of school effects

Through an analysis of gains in mathematics achievement between the tenth and twelfth grades for respondents to the National Education Longitudinal Study of 1988, we examine Coleman's explanation for why Catholic schools apparently produce more learning than public schools. According to Coleman, Catholic schools benefit from endowments of social capital, generated in part through greater intergenerational social closure (i.e., dense network connections between the parents of students). Instead, we find that for public schools, social closure among parents is negatively associated with achievement gains in mathematics, net of friendship density among students. This evidence of a negative effect of parental social closure within the public school sector lends support to our alternative hypothesis that horizon-expanding schools foster more learning than do norm-enforcing schools. Moreover, this result renders social closure incapable of explaining any portion of the Catholic school effect on learning, even though within the Catholic school sector there is some evidence that social closure is positively associated with learning.