Purpose: Through case studies of five states with varying facilities policies, this study examines the factors contributing to expanded state investment in equitable public school facilities and how those factors can be leveraged to encourage states that make minimal investments to expand their support for facilities funding. Methods: Data collection consisted of a literature review of existing research on educational facilities taxation mechanisms, spending practices, and public debt policies; case study data collection included policy document analysis and 44 interviews with school finance and facilities experts, including researchers, lawyers, consultants, practitioners, and state level staffers. Five case study states included Texas, Wyoming, New Jersey, Massachusetts, and Ohio. The conceptual framework utilized the lenses of critical policy analysis and fiscal sociology. Findings: The "Equity Investment Typology" categorizes 11 factors that contribute to expanded state investment in equitable public school facilities based on the extent to which they promote equitable investment. Factors are broken down into three categories: state spending, taxation, and public debt. Applying the typology to the five case study states revealed that states with various constraints and policy preferences have taken different policy pathways to expand their investment in educational facilities and maintenance. Wyoming and Massachusetts emerged as states with more equitable facilities funding systems. Best practices include conducting frequent statewide facilities inventories; distributing state aid based on a comprehensive set of factors, including local ability to pay and facilities needs; relying on a diversity of revenue sources, collecting taxes statewide, rather than solely from disparate local tax bases; providing state programs for debt payment assistance; and relying at least partially on pay-as-you-go funding mechanisms for facilities. Implications: Examining state facilities policies revealed important insights about how policies promoting equity have developed in certain states and points to opportunities to improve equitable access to facilities for students in other places. Currently, the quality of a child's school building is directly related to the decisions their state's policymakers have made in the past. While wealthy communities have the ability to adequately maintain their facilities, persistent patterns of racial and socioeconomic segregation have long-lasting implications for equitable infrastructure investment, particularly when funding is still tied to local property wealth in most states. Facilities advocates should push for federal funding for educational facilities as an integral part of national investment in infrastructure as well as for policy changes at the state level that include adequate and equitable state investment in facilities construction and maintenance. [For the Executive Summary, see ED591719.]