Discussion of inequity in funding of Pennsylvania schools has tended to focus on differences between wealthy and poor school districts. In Pennsylvania, 180 school districts have filed a lawsuit challenging the constitutionality of the existing public school funding scheme. A study of the state's 500 school districts, grouped by market value of taxable property and personal income, examined another problem. From 1986 to 1991, poorer districts were forced to increase taxes to support schools while wealthier ones were able to reduce taxes. Since wealthier districts have faster-growing economies, their tax revenues for schools have grown faster than those in poorer districts. Consequently, poorer districts suffered a greater tax strain than wealthier ones. The state attempts to offset differences in district wealth through the Equalized Subsidy for Basic Education (ESBE). A National Conference of State Legislatures (NCSL) report recommends a three-tier approach to Pennsylvania school financing: (1) all districts would receive state funds for basic educational costs; (2) funds would be apportioned in relation to district-aid ratios; (3) and some funds would be raised solely by districts. Disparities in tax burden between districts is expected to worsen unless the state becomes involved in finding a solution. (JPT)