SLIDE: The School Librarian Investigation—Decline or Evolution? is an exploratory project by Antioch University Seattle and funded by the Institute for Museum and Library Services [IMLS] for $348,905, to be conducted from September 2020 through August 2023. The research will determine patterns in the continuing, national decline in school librarian positions and how school districts decide to staff library, learning resources, and instructional technologies programs for K-12 students.
There is state survey data about state requirements for facilities and staffing. The page with the state data includes links to the NCES [National Center for Educational Statistics] data.
There are data tools to allow districts to compare themselves.