One in three children are not proficient in numeracy or literacy, according to this year’s Naplan results, leaving Australia “well behind” their international peers.

Almost 1.3 million students across more than 9,400 Australian schools and campuses took the national assessment program for those in years 3, 5, 7 and 9.

The Naplan results revealed stark discrepancies between boys and girls, with males struggling in literacy subjects across every age group.

There was also a deep divide between Indigenous and non-Indigenous students, and students with parents in professional and other kinds of work and jobs.

Nick Parkinson, an education specialist at the Grattan Institute, called the results “sobering” and “frankly disappointing”.

“What troubles me about this year’s results is that a third of students are still falling through the cracks. For a country as prosperous as ours, that is frankly disappointing.

“Naplan just tests Australian students, but what it tells us about the number of struggling students is similar to international tests like Pisa. And Pisa shows us we have a way to go to catch up to world leaders such as Singapore.”

Conducted every three years, Pisa is an international assessment of 15-year-olds in reading, mathematics, and science literacy.

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Stephen Gniel, the chief executive at the Australian Curriculum, Assessment and Reporting Authority, was more upbeat.

He described the results as “stable” and rejected claims the outcomes represented a stagnation of Australian education standards.

He pointed to schools still adjusting to changes made to the measurement scale and proficiency levels, introduced last year.

“National data rarely shows any significant change over a single year,” he said.

The trends in Naplan data are likely to take several years to emerge, he added.

Here are five key takeaways from this year’s test results:

Girls outperform boys in writing

Across age groups and location, girls consistently performed better in literacy and boys did better in numeracy.

Girls outperformed boys by a considerable margin in writing, with higher percentages of female students at “strong” or “exceeding” levels. This was evident in 73% of females compared to 58% of males in year 7, and 69% of females to 53.1% of males in year 9.

But in numeracy boys performed better, with 5.9% fewer female students in year 3 and 6.7% fewer females in year 5 achieving “exceeding” compared to males.

Parkinson said these results “worried him”, particularly the rate of boys not meeting proficiency in writing.

“That means one in about every two boys in year 9 were struggling to convey meaning in their writing,” he said.

“Some of that is down to how students are engaged in the social way we talk about these subjects.

“It’s about building a love of reading and writing early for young men.”

NSW and Victoria outperform other states

There were significant differences across states and territories, with students from New South Wales and Victoria routinely outperforming students from the rest of the country.

The results in numeracy in year 9 were a good example of that. Only NSW and Victoria recorded over 10% of results in the “exceeding” category for the subject.

They were closely followed by Western Australia on 9.3% and the ACT on 8%.

Queensland and South Australia both achieved less than 6%, while the Northern Territory and Tasmania less than 5%.

Indigenous students score lower in literacy subjects

Across age groups and states, Indigenous students scored lower in literacy subjects, with the gap in the “exceeding” category reaching up to 6%.

In year 9, the gap in “exceeding” for writing between Indigenous and non-Indigenous students measured 15.6%.

In writing it was 16.9%, in spelling it was 13% and in grammar it was 14%.

Across age groups in reading, about one in three Indigenous students were in the “needs additional support” level compared to fewer than one in 10 of non-Indigenous students.

That result was echoed in numeracy across all age groups.

Parkinson said the results showed Australia was “really failing” Indigenous students.

“There are many different factors here, and some of them are … really quite complex factors, but the fact that we’ve got nearly 60% of students, on average, not proficient in literacy and numeracy … should be kind of keeping education leaders up at night.”

Students with parents in skilled professions score higher

The results also tracked socioeconomic demographics through the employment status of parents.

They compared students with parents who worked as senior managers and professionals with students whose parents worked in manual, office and sales jobs.

The results showed an obvious difference in all five domains, with students in the former category consistently outperforming their counterparts.

In grammar and punctuation, the gap between year 3 students with parents in the senior managers and professionals occupation group and those with parents in the unskilled manual, office and sales occupation group was 25.1%.

In year 5 it was 17.1%; and year 7 it jumped to 22.6%. In year 9, the gap was highest, at 24.3%.

Achievement drops in high school

Finally, the level of the students’ results dropped as they got older.

Across all five domains, results steadily deteriorated. The percentage of students achieving “exceeding” and “strong” in reading increased from year 3 (66.3%) to year 5 (71.4%), then dropped in year 7 (67.3%) and 9 (63.0%).

The same trend played out in numeracy, with the percentage of students achieving “exceeding” and “strong” increasing from year 3 (63.5%) to year 5 (67.8%), remaining relatively stable in year 7 (67.2%) and dropping in year 9 (63.4%).

Parkinson said research showed results often drop off in high school.

“Students are more likely to be on track when they’re in primary school, when they’re engaged with school, when their attendance is higher.”

He said children “struggle more” in secondary school.

“That is due to something called the Matthew effect, which is like when the rich get richer and those who struggle tend to fall a little bit more behind.”

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