Emergent ethnographic research disentangles "social capital" from other components of social class (e.g., material and human capital) to show how class-stratified parental social networks exacerbate educational inequality among schoolchildren. The authors build upon this research by using survey data to reexamine whether certain forms of parental social capital create educational advantages for socioeconomically privileged students vis-a-vis their less economically fortunate peers. By drawing a distinction between the availability of social capital and its convertibility, the authors find that whereas larger stocks of parental social capital accompany higher rungs on the social class ladder, its educational utility is less clearly associated with class status. A possible exception to this pattern pertains to the educational utility of middle-class parents' ideas about the collective efficacy of influencing school policies and practices. At issue is whether a more inclusive understanding of the material and "sociological" reasons for educational inequality can spur educationally useful social exchange among parents across social class boundaries. (Contains 3 figures and 29 notes.)