Sheila E. Murray (Texas A&M University, Bush School of Government and Public Service), Kim Rueben (Tax Policy Center) & Carol Rosenberg (Tax Policy Center) have published State Education Spending: Current Pressures and Future Trends, 60 Nat’l Tax J. 325 (2007).  Here is the abstract:

Education expenditures are one of the largest spending areas for state and local governments, and per–pupil expenditures have been growing over time. We examine trends in state aid for education and overall education spending and decompose the existing drivers behind growing state costs. We then explore how predicted future demographic trends will affect education spending levels, as the percent of the population that is of school age falls. We conclude that there will continue to be a large state role in education funding, but demographic changes may lead to reduced political support for schools in the future.