Scholarly work on student and school performance poses a variety of explanations for observed variations. One explanation receiving too little attention is social capital, an intangible resource argued to grow out of social relations and social structure. The seedbed of social capital is argued to reside with John Dewey, who in 1900 used the term when explaining the importance of reading, writing and arithmetic to the future of individuals and communities. This paper examines social capital as a concept and discusses indicators and linkages that may be valuable to educators seeking ways to raise student and school performance. (Contains 4 online resources.)