Parents have a legal right to take a child from school - but there's hope better communication will stop them lining up at the gate.

A report listing issues schools encountered during the city-wide lockdown in Christchurch on March 15 during the mosuqe shootings.

The report cites communication as a major failure. It also mentions staff members had to deal with aggressive and concerned parents.

Principals Federation president Whetu Cormack told Heather du Plessis-Allan parents legally can take their child from school but lockdowns are special circumstances.

"When there is a lockdown, the school has tried to keep all the students safe, so we hope going forward that families will understand what their role is when this occurs."

The report has also found some schools thought a Police alert was a hoax, and that principals missed a Ministry email alert.

Cormack says that that there will likely be changes in that area as well.

"The Ministry has recommended they fast track this notification system, which I assume will be via text messaging."