Christchurch children are becoming "moving targets" between schools as post-quake issues force families to regularly move house.
Schools are experiencing massive roll changes each year as families living in damaged rentals go in search of homes across the other side of town.
Experts warn that too much transience for children can put their learning back about three months with each move to a new school.
Linwood Avenue School had 180 pupils on its roll of 300 come and go last year.
Principal Gerard Direen is concerned about disruption to children's learning as families struggle with housing issues and rising rent, particularly in the city's east.
"They're going all over the show, and coming from all over the show, both within Christchurch and leaving. There's a level of change that goes on that isn't OK."
Schools and teachers had to think "on your toes" to assess the needs of children who were "moving targets" between schools.
Since the quakes, the school had about a 50 per cent turnover within its roll. It was "definitely a risk" for the children's learning.
Parent Adrienne Hiscoke said her family were being monitored by authorities because of "transience concerns".
She, her partner and five children had moved all over the South Island hunting for work. Her oldest son, 6, had separation anxiety and anger problems after moving between five different schools.
"When you take him to school he cries and tries to run after us, and when he was last at school he ran away."
It made her "feel real bad", and she hoped to find a permanent rental property in the area so he would not have to move schools again.
Avondale School principal Mark Scown said transience in lower-decile schools was always of concern, but colleagues were now reporting a "significant amount".
Transience in his school was "certainly noticeable", and children were more dysfunctional than before, he said.
"If you've got children who, by the time they're 9 or 10 have been in five, six or seven schools, it can only negatively affect their learning."
Banks Avenue School principal Murray Edlin said some families even had to move outside the city during repairs.
"It certainly is a disruption for the kiddies when their lives are pretty disrupted anyway."
Canterbury Primary Principals' Association president Rob Callaghan said transience was the "nature of Christchurch at the moment".
Pupils with a long list of schools behind them often had "tell-tale" signs of lack of achievement and trouble socialising, and some research said a child could lose about three months of learning with each change of school, he said.
"The impact of a child regularly shifting from one school to another will be detrimental to their learning and their social well-being as well."
American Psychological Association research found frequent relocations in childhood related to poorer wellbeing in adulthood, especially for more introverted or neurotic types.
Registered psychologist Jane Millichamp said, despite it being hard to study, experts could glean that upheaval and inconsistency in children's living arrangements was disruptive and could do harm, even with strong family support. School support gave stability and resilience.
In Christchurch, the post-traumatic stress from the earthquakes, and the moving that occurred afterwards, was a "double whammy".
"For children, having much less control over their livelihood and where they live has got to be a factor for them in terms of risk."
- © Fairfax NZ News