We use population-level data on all Florida children born between 1994 and 2002 to examine the long-term effects of prenatal exposure to environmental toxicants from a Superfund (toxic waste) site. We compare siblings who faced different toxic exposures during gestation because of Superfund site cleanup (or, in other specifications, because of a family move). Children exposed to toxic waste while gestating have substantially worse cognitive and behavioral outcomes than do their unaffected siblings. These results are much larger than what would have been predicted were the effects of Superfund site exposure operating solely through standard measures of birth outcomes.

Little is known about the role birth order plays in delinquency and adult crime outcomes that carry significant externalities. We use rich data sets from Denmark and Florida to examine these outcomes and explore potential mechanisms. Despite large environmental differences between the areas, we find remarkably consistent results: in families with two or more children, secondborn boys are 20%–40% more likely to be disciplined in school and enter the criminal justice system than are their firstborn male siblings. We rule out health at birth and school quality as mechanisms but find evidence for the role of parental time investment.

We make use of a new data resource--merged birth and school records for all children born in Florida from 1992 to 2002--to study the relationship between birth weight and cognitive development. Using singletons as well as twin and sibling fixed effects models, we find that the effects of early health on cognitive development are essentially constant through the school career; that these effects are similar across a wide range of family backgrounds; and that they are invariant to measures of school quality. We conclude that the effects of early health on adult outcomes are therefore set very early.

Recent evidence indicates that boys and girls are differently affected by the quantity and quality of family inputs received in childhood. We assess whether this is also true for schooling inputs. Using matched Florida birth and school administrative records, we estimate the causal effect of school quality on the gender gap in educational outcomes by contrasting opposite-sex siblings who attend the same sets of schools--thereby purging family heterogeneity--and leveraging within-family variation in school quality arising from family moves. Investigating middle school test scores, absences and suspensions, we find that boys benefit more than girls from cumulative exposure to higher quality schools.