There is no such thing as a perfect state school aid formula. Different people define equal educational opportunity differently and school aid formulas include a variety of criteria and incentives that result from compromise and majority voting after being "hammered out" through the political process.
This paper is published in Edelman, Mark A., and James J. Knudsen. A Background Report: School Aid Goals, Parameters, Formulas and Impacts Under Declining Enrollment. Iowa State University, 1988.
Edelman, Dr. Mark A. and Knudsen, James J., "A Background Report: School Aid Goals, Parameters, Formulas and Impacts Under Declining Enrollment" (1988). Economic Staff Paper Series. 217.