A major international test has ranked New Zealand teens ninth in the world for reading, 10th-equal for science, and 14th-equal in maths.In all three subjects the OECD's Programme for International Student Assessment placed this country's 15-year-olds in a group of strongly-performing countries sitting below a group of world-leaders.But the results also showed New Zealand boys' proficiency in reading has continued to fall, dragging down the national average for the subject.The Education Ministry said New Zealand's sample was skewed toward higher-achieving students, meaning the country's average scores might be inflated by 10-15 points."It is important to note that the bias may not affect trend or country comparisons to its full extent, because a similar (although, likely, smaller) bias may also affect past results and the results of other countries and economies," it said.In reading New Zealand's score of 497 was slightly below its previous result of 501 but good enough to put it ahead of both the UK and Australia in a group of seven countries just below the top three of Singapore (535 points), China, and Taiwan.In science, New Zealand was 10th-equal with Australia on 509 points, an improvement of five points, but well behind world-leader China which scored 597 points.In maths, New Zealand's score improved by a single point to 480 while the OECD average dropped to 463.That put New Zealand 14th-equal with Ireland and Belgium, just ahead of Australia (478) but behind the UK (488) and well-behind chart-topping China on 612.SuppliedThe 2025 tests also included "computational thinking" which measured students' ability to use computing tools to present data and answer questions.With an average score of 531 points, New Zealand teens were just one point behind Australia in 10th position.More than 700,000 students in more than 90 countries sat the PISA tests last year.Science was the major focus of the assessment, meaning students and their schools were asked extra questions about the subject.Most New Zealand students believed they could explain how carbon-dioxide emissions affected global climate change easily (29 percent) or with a bit of effort (40 percent).They were a bit less confident about describing the role of antibiotics in disease treatment - 14 percent saying they could do it easily and 42 percent with effort.The study found New Zealand students who enjoyed science performed better by about 25 score points than those who did not, as did those with higher levels of curiosity.New Zealand students who indicated high levels of perseverance scored 13 points better."The findings in this chapter suggest the typical New Zealand learner in PISA enjoys science and is more curious than average. However, the average student in New Zealand does not rate their perseverance highly, nor their adaptability to new or challenging situations," an Education Ministry report on the science results said."New Zealand students had an average of 4.4 hours of science learning per week. More time on science homework was associated with lower science scores, but there was no score difference associated with more time on homework across all subjects."The study found the average science test scores of New Zealand students from the poorest backgrounds improved 20 points since the previous test to 473 points, narrowing the gap with those from the richest backgrounds to 91 points.A graph showing how New Zealand students' science results compare internationally.SuppliedThere was little difference between boys' and girls' science scores, but boys performed significantly better than girls in maths (a 12-point difference).In reading boys' performance dropped 11 points since the previous round, widening the gap with girls to 34 points.Māori students' average score improved 10 points in science, remained about the same in maths and fell slightly in reading.Pacific students' average score in science jumped 15 points, improved slightly in maths, and remained about the same in reading.The OECD said the tests showed students were finding it harder to read longer texts and to answer questions involving multiple sources of information.The ministry's report on the science results said New Zealand students had an average of 4.4 hours of science learning per week and most (69 percent) said they had less than 30 minutes science homework each day."New Zealand students reported a slightly lower overall average daily time on all homework, 1.2 hours compared to the OECD average of 1.4 hours," the report said.It said New Zealand students said they spent 2.5 hours a day using digital devices for learning, higher than the OECD average of 1.7 hours."Students reporting very low amounts of learning time on devices had lower science scores than their peers reporting more time learning on devices," the report said."More leisure time on devices at school was associated with lower science scores."The report said more New Zealand 15-year-olds reported being distracted when using digital resources in most or every science lesson than the OECD average (38 percent compared to 28 percent) but unlike the rest of the OECD in New Zealand there was no significant score change.The report said New Zealand students used AI for learning at a similar rate to the OECD average but were less likely to use it to draft text for assignments.It found that the number of New Zealand school principals reporting shortages of digital devices had doubled since the 2022 assessment to 17 percent.