The Arizona Department of Education made a massive mistake in Title I funding, which is money slated for low-income students.
That error could cost Tucson Unified School District about $2.5 million.
TUSD is not the only school district that could be on the hook for overpayments.
The Arizona Center for Investigative Reporting reports a miscalculation of $62 million over the span of four years.
In Pima County, Sunnyside School District was overpaid $1.7 million.
The amounts for other districts range from $11,000 to nearly $500,000.
The Arizona Department of Education has not revealed yet how it will handle the overpayments.