Being underprepared and not getting enough sleep are reasons why New Zealand school children are lagging behind their international counterparts, research has found.
Maths is a particular problem area, with more than two-thirds of primary school children lacking the necessary background knowledge for lessons - and their teachers admitting a lack of confidence to teach the subject.
The findings are contained in a Ministry of Education analysis of global education rankings known as the Trends in International Mathematics and Science Study (TIMSS) and Progress in International Reading Literacy Study (PIRLS).
Seventy-six per cent of Year 5 students (aged 9 and 10) were identified by teachers as lacking some or a lot of the necessary background knowledge for maths lessons.
NZ Principals' Federation president Phil Harding said that was a common gripe of teachers at all levels, however maths, in particular, was a subject under the spotlight.