She couldn't say how regularly students were having food delivered, but said it was a noticeable number.
The main issue with the deliveries was security, rather than health concerns. The school, with 2214 pupils, has an on-site canteen.
"(Health) is probably a factor, but we're not even going there. We're just discussing it at the moment," she said.
"I wouldn't say we won't implement an outright ban, but right now we're simply encouraging students to make and bring their lunch."
She believed other schools were facing a similar issue.
The school's Board of Trustees chair Michelle Alexander said the issue was raised at the board's last meeting about a month ago, and it would be considering the issue at future meetings.
Any possible ban would be considered with input from a student trustee, and she admitted that "times were changing" and that it could be convenient for pupils to order food online.
"I think we need to get more facts about it before we can say (if a ban will be imposed). It's all about making an informed decision. If there's a general need for it we need to look at why we can't offer the same options through the school canteen.
"It's about giving the students what they need. We don't want any child going hungry, but equally we want them to be safe."
UberEats, a service that allows people to order food from a selection of cafes and restaurants and have it brought to them by a driver, was launched in New Zealand in March after beginning in the United States.
McDonald's joined the app, meaning in central Auckland suburbs it's possible to order from the fast food giant for a $6 fee.
Across the ditch, a number of schools in Australia have followed the same route, banning delivery drivers from entering school grounds because of security concerns.
New Zealand School Trustees Association Lorraine Kerr said she had never heard of pupils having food delivered, and it was possibly a problem unique to Auckland.
"It's not common, I can tell you that. The school is right- they have the absolute right to ensure every student is kept safe and if there's people coming and going it would be nigh impossible (to ensure).
"I also know that schools are doing their darnedest to ensure healthy eating."
An UberEats spokesman said customers had to be over 18 to order food and where necessary delivery partners were advised if they were banned from entering private property.
All delivery drivers had to pass a criminal history check, he said.