PHOENIX ‑‑ The amount of tax dollars that ends up in Arizona classrooms slid again last year to the lowest level since this spending has been monitored.

New figures Tuesday from the Auditor General's Office found that slightly less than 56 cents of every dollar was used for what is considered "classroom instruction.''

That includes salaries and benefits for teachers, aides and coaches. It also covers supplies like pencils and paper, athletics, and activities like band or choir.

But the situation is even more acute than that.

The declining percentage that wound up in the classroom comes on a smaller base, with the total amount of money available for all types of spending slipping between 2009 and 2010. Auditor General Debra Davenport listed total operational spending per pupil for last school year at $7,609, compared with $7,908 the year before. And Arizona remains close to $2,500 below the national average in per pupil spending.

Attorney General Tom Horne, who was state school superintendent for the last eight years, said the central number in the report ‑‑ that 55.9 percent figure for classroom spending ‑‑ is based on a flawed premise of what are and are not classroom costs, with the idea being that everything else is administrative.

"The measure that they're using counts as administrative costs things that pertain very closely to the education of the students, including nurses, psychologists, transportation to get them to school, air conditioning to keep them able to learn,'' he said.

That view is shared, at least in part, by John Huppenthal who replaced Horne in January. He specifically said audiologists, speech pathologists and counselors are part of classroom instruction.

Huppenthal also noted the report has positive news: Spending on pure administrative costs ‑‑ superintendents, principals, business managers, clerical staff and human resources ‑‑ is only 9.5 percent. The national average is 10 percent.

But when other non‑classroom expenses are examined, the state does not fare as well.

On average, Arizona schools spend more than the national average on what is considered student support, including counselors, social service workers and even attendance clerks.

Davenport said that may be linked to economics: The most recent figures show 21 percent of children in Arizona live below the federal poverty level, compared with 18 percent nationally. Schools in Arizona also spend more than the national average on energy.

Davenport said her staffers, looking specifically at the districts with the highest energy costs, found they had excess building space as enrollment has not kept pace with expectations and, in some cases, there actually are fewer students. She said that, until recently, districts appeared to be reluctant to reduce excess space.

"Decisions to close buildings or schools can be difficult or painful,'' Davenport said. But she said district officials have to make that decision, as the amount of state aid they get is based on the number of students, not the square footage of the buildings.

"By continuing to operate schools far below their designed capacity, school districts are wasting available operating dollars that could otherwise be spent on instruction or instruction‑related programs,'' she wrote.

Davenport said more than just percentages are involved.

On a pure cash basis, she said total spending on school operations increased by 47 percent between 2001 and 2009 before declining by 4 percent this past school year. All totaled, Davenport said, Arizona's per‑pupil spending remains nearly $2,500 less than the national average.

The bottom line, then, becomes that the higher expenses for some non‑academic areas, coupled with the latest drop in actual dollars available, leaves less to spend in the classroom. And Davenport said that results in larger class sizes.

In 2008, she noted, Arizona districts averaged 17.3 students for each teacher. At that time the national average was 15.

Now, she said, the Arizona number is up to 17.9. No comparable national figures are available.

Horne said he has consistently believed the state is not putting as much money into public education as it should. He cited the annual report from Education Week magazine putting Arizona 49th of the states.

Huppenthal said the state's lean spending should be seen as an asset to encourage "innovative ideas'' on how schools can change teaching methods.

"What we have to have is ideas that can help them get greater academic gains and lower spending,'' he said. That includes "blended classrooms'' where students from multiple grades are combined but can proceed at their own rate, often with the use of digital learning as well as classroom instruction.

Davenport said funding numbers are more than academic.

"Available evidence supports a positive link between the percentage spent on instruction and student achievement,'' she wrote. In fact, she said, this can even overcome out‑of‑school factors like poverty: On average, districts that directed more of their funds to classroom instruction had higher passing rates on the Arizona Instrument to Measure Standards tests.