McCarthny said the Tangis were "first and foremost a school family".
"They're just a good solid family, who not only support their own family, but the school and other children."
The principal said the kids had been back at school, and it was "a good place for them" as it provided a consistent and supportive environment.
McCarthny felt Tevita's death hadn't sunk in it yet for the children.
"Because they're so young, I don't think it's hit home yet for the kids. It probably won't for a while."
The principal said in dealing with loss and emotional hardship, the school dealt with each situation differently.
"We look at what we can do from a school point of view. From an emotional point of view we look at how class teachers can support them."
McCarthny said Tevita's wife had been "quite remarkable, dealing with her own sorrow while also being a mother to four young children".
He said they were a "wonderful family", with solid values.
"They're a really good, really nice family ... They're from modest means, but have always supported their children in any way they could."
A Givealittle page set up for the family by St Heliers School had been flooded with support.
The page was set up today and has already raised over $10,000 for the Tangi family.
McCarthny said he was and wasn't surprised at how much money had been raised in such a short space of time.
"People in the school community and wider community have been so generous. But Kiwis are just really generous people. Everyone rallies around when someone's hurting ... You just think, 'how would you feel if it was you?'"
McCarthny said the family was taking things day by day.
"If we can support them at all, that would be fantastic."
You can donate to the family at: https://givealittle.co.nz/cause/shstangifamily
