The association between family disruption and child socio-emotional and behavioral development is a relatively well-examined but as yet unresolved issue, and the conclusions of previous research have been ambiguous. Further, some studies have indicated that associations may depend on other risk factors, yet the question of heterogeneity has been relatively little discussed. The purpose of this cross-sectional study was to assess associations between family disruption on the one hand and teacher-rated and self-reported outcomes on subscales from the Behavior Assessment System for Children, 2nd edition (BASC-2) and the Behavior and Emotional Screening System (BESS) on the other, among a Danish sample of 817 normally developing schoolchildren. Specifically, we assessed (a) the extent to which background factors explained unadjusted associations and (b) whether associations were heterogeneous across the distribution of outcome measures. Results from ordinary least squares (OLS) models showed that relative to children from intact families, children from disrupted families had higher problem scores on BASC-2 subscales Externalizing Problems, Study Skills and School Problems even after controlling for a wide range of background factors. Quantile regression (QR) models showed that associations with Externalizing Problems and Study Skills were stronger among children with higher problem scores. Certain behavioral problems may therefore indicate increased vulnerability towards adverse events, such as family disruption. General screening for such problems could provide an opportunity to identify children in need of special attention and support against the potentially negative outcomes of family disruption for their school experience.