Social capital refers to the nature of ties within a social unit, as well as the unit's external relationships. We draw from organizational sociology and political science, and also build upon existing insights in school board research, to offer an approach that address the effects of "bonding" (internal ties) and "bridging" (external ties) by board members. We hypothesize that these two sources of social capital are positively associated with financial and academic outcomes at the district level. Results, based on data from 175 Pennsylvania districts between 2004-05 and 2006-07, support our hypotheses. Implications for research and practice are discussed. (Contains 3 figures, 3 tables, and 12 notes.)