The father said he had met school staff six times but felt they did not "own" the problem and implied he was overreacting.
Restorative justice meetings had been held but did not fix the problem, he said.
Waimairi board of trustees chairman Cory Bedford told the Herald no formal complaint had been received from the girl's father.
He was not aware of the contents of emails between the lawyers but he was aware communication had taken place.
"We have met with this parent to discuss the matter on a number of occasions. We are continuing to investigate his claims.
It was important to follow the proper process in handling any complaint of this nature.
"We've been saying 'make a formal complaint and go to the next level'. Until that happens we're hamstrung."
He said they were unable to discuss details of the matter publicly because of privacy issues.