When it comes to education – what works, what has gone wrong, who pays for it – the debate can get very emotional and, shall we say, evidence-free.
So here we assess some of the arguments put forward to explain why Australian students are going backwards on key global tests like PISA, released this week. Some have a higher degree of truthiness than others.
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What PISA says about Australian schools
The major global test of student achievement reveals just how far Australian high school students are behind their peers in the world's best performing countries.
Parents are the worst
Judy called me on Wednesday. She is an experienced teacher in a NSW region, fed up with what she saw as a glaring omission in the debate.
"If I had to pick one factor on whether or not a student was going to strive, perform well, get their homework done: it's the value that parents put on education," she said.
It's anecdotal, but she has a point that's borne out in the data. Longitudinal research from the University of Queensland shows that kids who grow up in a home with more books – as a proxy measure for how much their parents care about literacy and education – have consistently higher test scores.
If parents don't instil respect for the importance of learning, it's an uphill battle for teachers.
Chris Presland, the head of the NSW Secondary Principals Association, said "we have schools that are expected to do a lot of parenting for parents that are too busy or incapable of doing what they should be doing, and the end result is teachers that are just trying to do so much."
Kids today!
I know, right? With their Snapchat and their YouTube and their attitude? I mean, East Asian countries where the kids stand up when the teacher walks in, do their homework on pain of death and slave in night-time drill schools consistently beat us in these things.
Research shows a correlation between high-discipline environments and better test scores. It also shows that better student outcomes correlate with universal quality preschool access, which we don't really have.
Or maybe, as Canterbury Girls High student Paloma Jackson-Vaughan pointed out in a good piece for Fairfax this week, a non-compulsory, anonymised test the implications of which are entirely opaque is not something the average 15-year-old is going to invest a lot of mental energy in. Which leads us to our next point.
Smartphones have fried their brains
There is a groundswell of concern about the rise of the smartphone to total dominance in our waking lives. Digital technology is enriching, but also consumes our attention at the expense of books, outdoor activities and social life. What might that mean for developing teenage brains who have known no life without it?
Could obsessive use of digital media, as Nicholas Carr suggested in his Pulitzer-shortlisted 2011 book The Shallows, actually be rewiring our brains away from deep concentration and problem-solving toward infinite skimming and perpetual distractibility? Is this why the average 15-year-old can't solve problems her predecessors could 15 years ago?
Venerated Finnish education expert Pasi Sahlberg fears so. Pointing out that Finland's PISA results in reading have been in decline since 2009 without any other changes to the education system, he asks, "how else can you explain this dramatic change?"
High-performing Japan slipped a bit in PISA 2015 reading too, a result its experts blamed on digital technology.
The research is in its infancy because academia moves glacially compared to our digital overlords and their marketing armies in Silicon Valley. But a decade-long Canadian study, "Growing Up Digital", has reported disturbing preliminary results, with a majority of phone-obsessed students coming to school tired, distracted and unable to focus.
The PISA test is meaningless
Skeptics abound on the cultural bias, methodology and legitimacy of tests like PISA and TIMSS. How much can you really tell from a multilingual, sample-based test performed by a random selection of students, in a bunch of wildly different education systems?
Teacher and head of the Australian Tutoring Association Mohan Dhall argues there is limited value in country comparisons through PISA.
"They do not compare like with like," he said. "In Australia, teachers work with an incredible diversity of students, need to meet the needs of a wide range of learning styles and do not benefit from a culture of compliance evident in other nations ... Teachers here have a role that is far more demanding than in nations where students and their families vest everything in education and where tutoring is endemic."
We're actually not doing that badly
Look, we're still well above the OECD average. We ranked 14th in science, 16th in reading and 25th in mathematics, of 72 participating countries and economies.
We outranked the UK, the US and France in all three categories. And most of the countries ahead of us – with the exceptions of Canada and New Zealand – are small, monocultures like Singapore, Hong Kong and Finland. There are a lot more challenges educating a vast, diverse country like Australia.
This is all true and relevant for a sense of perspective, but none of it accounts for the internal decline in our scores.
The teachers are no good
There is "clearly something wrong" with our education system, federal Education Minister Simon Birmingham said this week after the PISA results. But what, exactly?
"The single greatest in-school factor in terms of student accomplishment is absolutely the teacher," he told ABC radio. "Our number one focus has to always be teacher quality and ensuring that our hardworking teachers are given the skills in their training years and then the support through ongoing professional development to be the best."
If the average Australian student is 10 months' schooling behind where they were 15 years ago in terms of their literacy skills, it seems reasonable to ask if the average Australian teacher is not teaching as well as they were then. This is not a popular argument with teachers, or the unions, although they have acknowledged doubts over the way universities have lowered entry requirements for teaching.
There is also a major problem with teachers teaching "out of field" in maths due to the shortage of qualified maths teachers.
We do know that high performing countries manage to attract top-tier students to the occupation – Singapore and Hong Kong draw teachers from the top 30 per cent of school leavers. In Finland and South Korea it's the top 10 per cent. But "Australia draws its teachers largely from the middle third of school leavers," writes the Australian Council for Education Research's Geoff Masters.
NSW has attempted to address that with reforms like requiring a minimum standard of three band-five HSC results for teaching degrees to ensure their results are in the top 30 per cent of the state.
The Grattan Institute's Peter Goss says the most important thing is continuing professional development of the existing teaching body. He says NSW's Targeted Teaching program, which started in 50 schools and is now in 400, is showing promising results. The program employs experienced instructional leaders full-time to coach other teachers – it's a way of finding out what's really going on in classrooms and working to improve it every day.
Funding has been going to the wrong things
Small class sizes cost more, and it's an easy winner with parents and teachers, but the research shows it makes little difference.
Or, as Andreas Schleicher, the OECD's top education honcho has said, if you have a choice between a small class size or a great teacher, go for the great teacher.
A Fairfax Media investigation revealed this year that yes, there are private schools that are over-funded. Some of our richest schools get millions above the School Resourcing Standard.
Private students get less taxpayer money per head than public students. But when limited taxpayer dollars have been going for years to schools that can afford to put cameras in their swimming pools while state schools have teachers buying supplies out of their own pocket, we have a problem.
It is overwhelmingly the public system where the neediest kids go to school. On 2013 figures, 82 per cent of low-SES students go to public schools, 12 per cent to Catholic and 6 per cent to independent schools. 84 per cent of Indigenous students and 77 per cent of kids with a disability are in state schools.
"We've spent a lot of money on education and haven't got the results for it that we wanted, but I think that is because the money isn't necessarily being directed where it will be most effective," said Dr Sue Thomson, a former teacher and the Australian Council for Education Research's resident PISA expert. "If it's in these high-achieving schools we might get a little more high achievement, but if we direct more of it to low-achieving schools we're more likely to get much more value for money. It's by lifting the low-achieving students you can lift the system."
Which leads us to the last and perhaps most salient argument.
Australia's system is too unequal
The bottom 25 per cent of Australian 15 year olds by socio-economic background are on average a full three years' schooling behind the top 25 per cent. This has not changed in the 15 years of PISA.
Why does a low socio-economic background disadvantage kids?
"It plays out because students don't have the resources that their more advantaged colleagues have," Dr Thomson said. "They don't have access to parents with the same level of education, they don't have homes with the same levels of resources, they might live in overcrowded conditions and not have room to study, or they may have parents who don't have time to help them or don't understand the value of education.
"They don't get read to as young children, they don't get experiences that other kids with money do. Kids in the bush might go to schools where they have complete turnover of teachers from one year to another. There's a whole raft of things."
This is why the Gonski needs-based funding model was designed to give additional loadings to disadvantaged kids.
Maurie Mulheron, head of the NSW Teachers Federation, said "I'm surprised that people are surprised. What the PISA results have confirmed are the findings of the Gonski review. Australia has the largest concentration of disadvantaged students in disadvantaged schools. That means those schools are almost the emergency wards of the health care system, that requires a very intense set of resources to combat intergenerational poverty."
High quality and high equity systems are the ones that do the best in the world.
At the launch of the 2015 PISA results in London this week, OECD Secretary-General Angel Gurría said "in Japan, Hong Kong and Estonia, the 20 per cent most disadvantaged students do as well as the average student in the OECD area.
"And we know how they do it. They set high and universal expectations for all students. They keep an unwavering focus on great teaching. They target resources on struggling students and schools. And they stick with coherent, long-term strategies."