The question isn’t how much? but rather for what? A couple of days before the Australian government released its Review of Funding for Schooling this week, the Organisation for Economic Cooperation and Development published an attempt to answer the question Does Money buy strong performance in PISA?

The Australian report was full of calls for increased government spending, perhaps an extra $5 billion a year. The OECD’s report concluded that the countries with the best educational outcomes were not those that spent the most money.

What closely links the two reports is the Programme for International Student Assessment (PISA) that the OECD developed and that the Australian review used to justify its belief that more money is needed.

Says the Australian report in its executive summary:

Overall, Australia has a relatively high-performing schooling system when measured against international benchmarks, such as the Programme for International Student Assessment. However, over the last decade the performance of Australian students has declined at all levels of achievement, notably at the top end. This decline has contributed to the fall in Australia’s international position. In 2000, only one country outperformed Australia in reading and scientific literacy and only two outperformed Australia in mathematical literacy. By 2009, six countries outperformed Australia in reading and scientific literacy and 12 outperformed Australia in mathematical literacy.

Says the OECD:

In education, as in everything else in life, you get what you pay for. Right? Well, as in everything else in life: not necessarily. As many OECD governments are poised to trim public budgets and cut expenditures, parents, educators and policy makers can take some comfort from PISA findings that show that the success of a country’s education system depends more on how educational resources are invested than on the volume of investment. The countries that are the strongest performers in PISA are not the wealthiest, nor do they allocate more money to education.

The difference in approach of the two reports is quite marked and the OECD’s conclusions should make governments wary about expanding their budgets to find the extra billions being asked for.

Some of those OECD findings:

PISA results suggest that above this threshold of USD 20 000 in per capita GDP, national wealth is no longer a predictor of a country’s mean performance in PISA. The amount these high-income countries spend on education is similarly unrelated to their performance in PISA. A country’s/economy’s cumulative expenditure on education is the total dollar amount spent on educating a student from the age of 6 to the age of 15. After a threshold of about USD 35 000 per student, that expenditure is unrelated to performance. For example, countries that spend more than USD 100 000 per student from the age of 6 to 15, such as Luxembourg, Norway, Switzerland and the United States, show similar levels of performance as countries that spend less than half that amount per student, such as Estonia, Hungary and Poland. Meanwhile, New Zealand, a top performer in PISA, spends a lower-than-average amount per student from the age of 6 to 15.

The strongest performers among high-income countries and economies tend to invest more in teachers. For example, lower secondary teachers in Korea and the partner economy Hong Kong-China, two high-performing systems in the PISA reading tests, earn more than twice the per capita GDP in their respective countries. In general, the countries that perform well in PISA attract the best students into the teaching profession by offering them higher salaries and greater professional status.

This relationship between performance and teachers’ salaries does not hold among less wealthy countries and economies, however. In all PISA-participating countries and economies, school systems that invest in higher teachers’ salaries tend to have larger classes. At the country level, PISA finds that the size of the class is unrelated to the school system’s overall performance; in other words, high-performing countries tend to prioritise investment in teachers over smaller classes.

Successful PISA countries also invest something else in their education systems: high xpectations for all of their students. Schools and teachers in these systems do not allow struggling students to fail; they do not make them repeat a grade, they do not transfer them to other schools, nor do they group students into different classes based on ability. Regardless of a country’s or economy’s wealth, school systems that commit themselves, both in resources and in policies, to ensuring that all students succeed perform better in PISA than systems that tend to separate out poor performers or students with behavioural problems or special needs.

The bottom line: Money alone can’t buy a good education system. Strong performers in PISA are those countries and economies that believe – and act on the belief – that all children can succeed in school. Among wealthier economies, those that prioritise the quality of teachers over smaller classes tend to show better performance. When it comes to money and education, the question isn’t how much? but rather for what?