NASHVILLE — About a quarter of Tennessee’s public school districts, 33 in all, spend more on administrative costs — such as principals and school directors — than the statewide average of 10.5 percent, according to a new comptrollers’ report.

The report, written by the Tennessee Comptroller’s Offices of Research and Education Accountability, examined the 2012-13 school year.

Why does it matter?

Lindsay Boyd, director of policy at the free market-oriented Beacon Center of Tennessee, said the study shows what happens when schools fail to prioritize what happens in classrooms and instead focus on administrative offices.

“Despite an 8 percent increase in statewide enrollment since 1999, state spending in the classroom decreased by nearly 4 percent during that same time period while administrative costs increased by nearly 2 percent,” Boyd said, citing a 2013 Beacon Center study.

As for the Comptroller’s report, released Friday, it said school districts most likely to have higher rates of administrative spending are either very large or very small.

These are usually municipal or special school districts — as opposed to county districts.

Among the report’s other findings:

  • About two-thirds of the higher-spending districts fall into the bottom fifth or the top fifth of districts ranked by enrollment size.
  • Seventy percent of the higher spending districts had central office administrator-to-student ratios above the statewide median of 4.4 administrators per 1,000 students enrolled.
  • Higher administrative spending districts are likely to have more sources of local tax revenue.
  • In 2012-13, Tennessee districts spent $868 million on administrative costs, including school boards, superintendents, principals and other central office and support services.
  • Tennessee spent more, as percentages of total spending, on instruction (classroom spending), instructional supports, general administration and school administration than the percentages spent by districts nationally, and, except for school administration, more than the Southeastern states.