Education leaders are disappointed by New Zealand's scores in an international test of 15-year-olds' skills in reading, maths and science.
The results are the lowest New Zealand has recorded since the Programme for International Student Assessment (PISA) began in 2000, though falls by other countries mean this country's rankings have improved.
New Zealand scored 513 points for science, placing it behind 11 other countries, 509 in reading placing it 10th, and 495 for maths, putting it in 21st place.
The government highlighted the improvements in New Zealand's rankings compared to other countries in all three subjects, and said the small drops in its scores were not statistically significant.
However, the scores were the lowest New Zealand had recorded since testing began in 2000.
Science was the major focus of the latest round and NZ Association of Science Educators president Chris Duggan said the result was disappointing.
"We've improved our rankings on the country comparison chart, but we have failed to improve our results from the last PISA as a nation," she said.
"Despite the Ministry of Education and Ministry of Business Innovation and Employment's curious minds initiative, which started three years ago, we've seen no improvement in the science knowledge of our 15-year-olds, which is really disappointing."
Ms Duggan said science literacy was increasingly important because science was the basis for nearly every tool that people used in modern society.
She said better science performance would help New Zealand punch above its weight in the global economy through more innovation.
But she said children from poor and immigrant backgrounds were struggling to achieve at a high level, which contributed to a tail of under-achievement.
Ms Duggan said children needed more opportunities to learn science at primary and intermediate school.
Society has a 'poor attitude' to maths
In maths, New Zealand's score of 495 points was nearly 70 points behind league-table leader Singapore - a lag equivalent to two years of education.
Jake Wills, the co-head of maths at Kapiti College, said the relatively poor result reflected society's attitude to the subject.
"It's not OK to say 'I can't read' or 'I can't write', but it's perfectly socially acceptable to say 'I'm no good at maths' and I think that's starting to trickle down through all these results that we're seeing," he said.
Secondary Principals Association president Sandy Pasley said teachers and principals would be disappointed with the results.
"I think we would be hoping we would make more progress than this," she said.
Ms Pasley said it might be time to review what was taught in maths and science.
"Always we've got to be looking at how we can do things better and particularly I think it's time to really review those curriculums particularly in maths, science, and see if what we are actually teaching in terms of content and the way we're teaching it is matching what the best practice is."
Ms Pasley said she would also like to see research into why New Zealand's scores had fallen in 2012 and what other countries were doing differently.
Call to address poverty to reduce achievement gap
Auckland University education lecturer Fiona Ell said New Zealand's scores had stabilised after a big drop in the 2012 round of testing.
Dr Ell said one positive was the number of New Zealand 15-year-olds who performed at the highest level in at least one subject.
"The share of top performers that we've got in at least one subject, we've got 20.5 percent which is comparable with some of the really top-ranked people," she said.
The results also showed a narrower gap between the average scores of rich and poor students than in the 2012 round of testing, but Dr Ell said it was still too big.
"There's plenty of evidence, and the OECD report's very focused on equity, that socio-economic status has a huge impact and I think we're going through a time of quite rapid social change in New Zealand where socio-economic status differences are being exacerbated and that's going to be reflected in education."
Dr Ell said poverty needed to be addressed, but schools also needed to focus on techniques that helped close the achievement gap between rich and poor.
The president of the Educational Institute, Louise Green, said the results reflected a serious problem with child poverty and inequality.
Ms Green said the government's education reforms had failed to deal with the problem.
"We need to put more resources into schools in high poverty communities to ensure all kids get the support they need," she said.
Education Minister Hekia Parata said the government had invested a lot in education, and new initiatives including clustering schools together to work on common problems should help improve performance.