New Zealand's 15-year-olds have hit new lows in the international PISA tests of reading, maths and science.

Photo: RNZ / Richard Tindiller

The country's average scores in all three subject areas fell slightly, continuing a slide that has been going on for more than a decade in the OECD's prestigious Programme for International Student Assessment.

The tests and survey conducted in 2018 also indicated New Zealand students' well-being had worsened, with one-in-five reporting they did not feel safe at school, more students saying they felt lonely, and more complaining of disorder in their classrooms.

New Zealand's average scores were 508 for science (down from 513 in 2015), 506 for reading (509 in 2015), and 494 for maths (495 in 2015).

The Education Ministry said the drop in scores since 2015 was not statistically significant, but it was worried by the long-term trend.

In the past 12-18 years, New Zealand's scores had declined by 23 points for reading, 22 points for science and 29 points for maths. The OECD estimated that 30 points was equivalent to one-year of learning.

Despite the ongoing decline, New Zealand's average scores were all above OECD averages and sufficient to place New Zealand among the better-performing nations in reading and science.

For reading it was ranked 11th equal with Sweden out of 79 participating countries and regions. The score was about the same as those of the US and UK but well behind China which scored an average of 555 for children in four participating provinces, and Singapore which scored 549.

In science, New Zealand's score was the 12th highest, just ahead of Slovenia and the United Kingdom and Netherlands. China led the table with a score of 590, followed by Singapore on 551.

In maths, New Zealand's average score was 27th, between those of Iceland and Portugal and behind league table leaders China (591) and Singapore (569).

The OECD said 600,000 students in 79 countries and regions sat the two-hour PISA test last year, including 6200 New Zealanders from 194 schools.

The major focus of the 2018 PISA tests was reading and the New Zealand results showed a gender gap of 29 points in favour of girls, down from 46 points in 2009.

The report said the performance gap between New Zealand's rich and poor students had narrowed from 104 points in 2009 to 96 points last year, slightly higher than the OECD average of 89 points, and few students from poor backgrounds performed at the highest levels.

"Some 25 percent of advantaged students in New Zealand, but 5 percent of disadvantaged students, were top performers in reading in PISA 2018. On average across OECD countries, 17 percent of advantaged students, and 3 percent of disadvantaged students, were top performers in reading."

Social inequality among factors

The Education Ministry's deputy secretary, evidence, data and knowledge, Craig Jones, said the main reason the gap between rich and poor had narrowed was that average scores for children from well-off backgrounds had declined more than the scores of children from poor backgrounds.

He said a range of factors was likely to have caused the long-term fall in New Zealand's scores, including falling enjoyment of reading among 15-year-olds.

"It's very strongly related to reading achievement and more kids are saying that they're just not reading for enjoyment anymore," he said.

Just over half of the students said they only read if they had to, 43 percent said they did not read for enjoyment, and 18 percent said they never read fiction.

Dr Jones said more students also reported that their classrooms were not good for learning.

"One of the other things that we're seeing in PISA this year is a lot more kids are saying that there are challenging learning environments so they say there is noise and disorder in the classroom or kids are not listening to what teachers are saying and that disciplinary climate is really important to effective learning outcomes."

Dr Jones said the tests found that students' sense of belonging had fallen in most participating nations including New Zealand. Fewer students agreed that other students liked them and that they felt like they belonged at school, and more said they felt lonely and awkward at school.

In addition, New Zealand had one of the worst scores for classroom behaviour of any OECD nation with more students reporting noise and disorder in their classroom (41 percent) and more saying students did not listen to their teachers (35 percent). The number of students who skipped school in the two weeks before the test also increased, to 29 percent.

The number of students who did not feel safe at school had increased from 13 percent in 2009 to 19 percent in 2018 and New Zealand had one of the highest rates of frequent bullying.

Dr Jones said the ministry was worried about the long-term decline in the PISA results. He said one of the highest-performing nations, Finland, also had long-term decline in its PISA scores as did Australia.

He said New Zealand should look at those countries with improving scores, such as the UK.

"They've certainly got a very strong focus on early literacy, and very strong focus on teaching of phonics in the early years," he said.

Dr Jones said the results were the culmination of ten years of schooling and it would be simplistic to blame the decline on the NCEA qualification.

"We need to be looking at what's happening all the way through schooling to understand what's driving the results that we're seeing among our 15-year-olds," he said.