The extended family forms the basis for orphan care and education in sub-Saharan Africa. Initial absence followed by emergence of differentials in primary school enrollment between orphans and non-orphans have been attributed to the strength and subsequent HIV/AIDS-induced breakdown of extended family orphan care arrangements. Yet, few attempts have been made to describe how these arrangements are affected by HIV/AIDS or how they relate to observed patterns of childhood outcomes by sex and orphan status. We use a combination of quantitative and qualitative data to show that maternal orphans but not paternal or double orphans have lower primary school completion rates than non-orphans in rural Zimbabwe, and that these patterns reflect adaptations and gaps in extended family orphan care arrangements. Sustained high levels of primary school completion amongst paternal and double orphans--particularly for girls--result from increased residence in female-headed households and greater access to external resources. Low primary school completion amongst maternal orphans results from lack of support from fathers and stepmothers and ineligibility for welfare assistance due to residence in higher socio-economic status households. These effects are partially offset by increased assistance from maternal relatives. These findings indicate that programmes should assist maternal orphans and support women's efforts by reinforcing the roles of extended families and local communities, and by facilitating greater self-sufficiency.