"However, this means some new entrants appear to be ill-prepared for the school environment."
Children had been sleeping with parents since the earthquakes began, and were absorbing adult anxieties and hearing adult conversations, which meant they were different in personality from pre-quake "typical" new entrants.
Children and adolescent psycho-therapist Sarah Robins said she was seeing many children traumatised by the earthquakes.
Ms Robins is a director of the Hara-keke Centre, which has a specialist team treating quake trauma in youngsters. The housing situation was a contributor to increased anxiety in homes, she said.
"[Children] are displaced from homes they can't live in any more or need to be repaired. What's more distressing for them is when they've moved in with family members and some children don't even have beds.
"Sleep is the major issue. I can understand how schools are having problems with inattention, because some children are not sleeping. This means they are tired during the day, finding it difficult to focus, which means that normal behaviours are more challenging."
Ms Robins said some children were going from uncertain housing environments into classrooms where their teachers might also be stressed because of their own housing issues.
The symptoms of post-traumatic stress included restlessness, avoiding certain places and being hyper-vigilant to noises. APN