"She had the joy of this, do you smell it?" he asks.
"I feel bad that the leading dignitary of our country has had to use that toilet - but our kids are just as important and they have to use that. But the exciting thing is that we don't have to be used to it any more."
A $47 million Government investment into fixing the school's leaky buildings announced by Ardern this week means the school can focus on other issues including fixing the state of its toilets.
As part of the redevelopment, the school will have brand new bathroom facilities including a new unisex toilet for children who identify as gender diverse.
"It opens up a lot of examples of things that we have just dreamed about that actually can become a reality," Gordon says.
DREAM COME TRUE
Another waft of musty, stale smell crawls up my nostrils as we walk into the science room.
"That is the dampness," Gordon says. "That smell is endemic through all of these buildings."
He is talking about the 59 soon-to-be demolished teaching spaces in the social science and business department, English, science and math blocks.
Outside the classrooms, the principal points to thick coats of paint which cover up the "ongoing" leaky building issues.
"As you can see there is still leaking all the way through. What we have done is just patched it up, but it is never addressed. That is a significant drain on our resources," he says.
"So the fact that we can rebuild will mean that it is a dream come true."
I ask him to fast forward five years and describe what he sees.
There are 59 new strong, durable and "state-of-the-art" open learning spaces in the heart of the school grounds where four leaky school buildings once stood.
There is a covered outdoor area for students to congregate where the leaky maths, English and science blocks once backed on to a gully.
"Because this land is deemed unstable, we would have this as kind of a beautiful congregation area for the students," Gordon says.
"When you go out and you buy a new set of clothes and they look good on you, you feel good about that," he says.
"We put brand new classrooms for our kids; we hope they will get as excited about their learning."
Gordon says the students have become accustomed to their surroundings - but they will now no longer have to learn in cold, damp, leaky classrooms.
"This is their norm but actually we can create a new norm that gives them, I believe, even greater aspirations," he says.
The future of the school facilities now looked bright.
"I am mindful we are not just building for these kids," Gordon says. "We are building for the next generation; we are building for kids 20 years from now."
Gordon inherited the school and all of its leaky buildings when he became principal at the beginning of this year.
He acknowledged former principal Dave Randell for his hard work over the years and thanked the Ministry of Education's Hayley Parkes for all her hard work in Wellington on the school's behalf.
"They have put a lot of energy into this and we are the lucky recipients of that," he says.
HOW WOULD YOU SPEND $47M?
Mia Gardiner, 14.
Mia Gardiner, 14
"It will be really good to have new buildings because it is not very nice being in a classroom where it's not homely. It is not nice to work in an environment where you don't feel comfortable. With new buildings, it will be a lot easier to work to our full potential. It sometimes gets quite cold and it is hard to focus when you are shivering. I hope the money will go towards making the classrooms a bit more stable and warm."
"I haven't experienced leaky classrooms but they are pretty cold and pretty hot in the summer and pretty damp as well. I think it would be a huge help for our education to be able to be comfortable in your learning environment."
Jese Somerville, 13.
Jese Somerville, 13
"I think some of the classrooms are definitely showing their wear and tear, specifically in the G Block. You've got floors that have holes in them and could be a potential danger to students. It would be good to get those fixed as well as be warm so we can focus on our learning and get the best out of school."
Deija Vukona, 14.
Deija Vukona, 14
"It would be pretty nice if there were places for us to sit at lunches and morning tea times because during the wet weather there is not that much cover to sit under. You end up sitting in corridors. And the school bathrooms. It would be good to have them fixed and made a little bit nicer."
"The heaters do not work and in the dance room we get water coming underneath. It is like a hazard when we are dancing because it can be very slippery and it gets really moist on the surface. It is really cold in the winter and hot in the summer and it is hard to focus. I think our school does need a bit of an upgrade."
