How State Education Funding Formulas Work
How states distribute K–12 education funding is one of the most consequential — and least understood — policy decisions in American education. Each state has its own funding formula, and the variation in design and outcomes across states is enormous. Understanding the basic architecture of these formulas is essential for anyone trying to interpret school finance data or understand why some districts receive more state money than others.
Foundation Formulas: The Dominant Model
The most common state funding approach is a "foundation formula." The state sets a per-pupil foundation amount — the minimum a district should spend — and then determines how much local property tax revenue a district can be expected to raise toward that foundation. The state provides the difference. A wealthy district with high property values may raise more than the foundation amount through local taxes and receives little or no state aid; a poor district raises less and receives substantial state support.
Weighted Student Funding
Many states have layered "weights" on top of their foundation formula: additional per-pupil funding for students who cost more to educate — ELL students, special education students, students in poverty, or students in small rural schools. A district with 100 low-income students might receive 1.2x or 1.5x the base foundation amount for those students. The generosity of these weights varies enormously across states.
Categorical vs. General Aid
Some state funding is "categorical" — restricted to specific purposes like transportation, special education, or career and technical education. Other aid is general, usable for any educational purpose. The balance between categorical and general aid affects how much flexibility districts have in responding to local needs. Heavy categorical systems can create perverse incentives: districts may identify students for special programs not because they qualify but because it triggers additional funding.
Local Revenue and Property Tax
The continuing reliance on local property taxes as the primary source of school funding is the root cause of most school finance inequity. Districts in wealthy areas can tax themselves at low rates and still generate abundant revenue; districts in poor areas tax themselves at higher rates and still raise less. Several states have faced legal challenges to property-tax-based systems — in some cases successfully (New Jersey, Kentucky, Wyoming) and in others not (Texas, Ohio). Browse per-pupil spending data across districts at district profiles and by state at the state browser.