Nearly a third of Rotorua students are struggling with the basics of reading and writing, an education expert says.
Describing the situation as tragic, Angela Gunn says 20 per cent have some difficulties with basic literacy and numeracy while a further 10 per cent suffer from chronic learning disabilities.
The director of Rotorua's Kip McGrath Education Centre says learning problems are "undiagnosed" and she blames the education system and the broad nature of the curriculum for letting students "fall through the cracks".
But Rotorua principals say under-achievement has more to do with transient local families and parents' attitudes to education than the curriculum, although they say schools need extra resources to support dyslexic students.
Mrs Gunn has raised concerns about the literacy levels of Rotorua students after assessing local teens who have left school without any qualifications.
In the past two years, she has found many have the reading comprehension age of an 11-year-old and the math skills of an 8-year-old.
The teenagers she assessed, aged 14 to 18, belonged to the city's Youth Transition Service, a service run by Te Waiariki Purea Trust which aims to get school leavers into training and help them find work.
She said their low literacy and numeracy levels were due to undiagnosed learning disabilities, such as dyslexia or Irlen Syndrome, a visual perception disability.
Thirty per cent of students she saw had some form of learning problem.
If not diagnosed early, students would "switch off" in the classroom, be labelled troublemakers and have major trouble learning at secondary school, she said. "A lot of the kids in that Youth Transition Service fit into that category.
"It's glaringly obvious to me their disability hasn't been picked up or seen to early on and it's a real tragedy.
"They have no chance at high school."
Mrs Gunn, who has been teaching for 19 years, said most teachers weren't trained to identify learning disabilities, making it too easy for children to "fall through the cracks".
When she left mainstream English teaching in 2001, she noticed some Year 9 students didn't have the literacy skills to cope at high school.
"Teachers do a fantastic job and I'm not blaming them - it's the curriculum at fault."
She said the primary school curriculum was too diverse and not enough attention was being paid to the basics of reading and writing.
But Rotorua Principals Association president Colin Watkins disagrees the problem is with the curriculum. Principals had been "crying out" for extra funding and resources to support students with learning disabilities and transient families and parents who did not value education were to blame, he said. "Education isn't failing children, social behaviours are.
"There are families who for generations haven't valued education and would rather play PlayStation with their child than take them to school."
Itinerancy was a major problem in Rotorua and greatly disadvantaged children by not giving them time to settle into school and learn. Mr Watkin said one local school, which he declined to name, had 112 children enrolled in Year 4 last year but only 14 continued into Year 5.
Literacy was the "number one" focus for Rotorua schools and their efforts were paying off, he said. An assessment last year of pupils at Years 3, 5, 7, and 9 at more than 40 primary schools found they had literacy skills at or above the national average.