Some are taught one-on-one bedside, both in hospital and in their homes. The remotely-based can sometimes receive tuition via webcam. When they are well enough, they attend the student support centre in Whangarei, which runs Monday to Thursday mornings.
In the classrooms, there is a steady hum of amicable activity with students sitting alone or in pairs, some with earphones on laptops, others poring over books. The kitchen area is often used by a food technology student, sewing machines are lined up in another corner. Several teachers will be with students, guiding their work. It's a place where students feel safe and free of judgement and they are used to people coming and going in the class, from specialists to parents and school counsellors.
There are the usual expected issues with absence, says Karen. "It takes a huge amount of energy to attend appointments, get to school and then concentrate."
However, there are some 'real high flyers achieving scholarships' at the school and Karen says there have been many success stories.
"A young man who was with us for anxiety and struggled to come in to the classroom, started this year at a new school with our support. He is now fully-transitioned into his new school and we have withdrawn him from here as he's doing so well."
Then there was the 15-year-old girl with high levels of anxiety around her own-age peers, who transitioned to NorthTec this year and is studying alongside older students, having obtained early exemption.
"She has just completed the first semester with three A-pluses and an A for her four modules. She also achieved 100 per cent attendance," says Karen proudly.
Although friendships can be difficult to maintain outside the school, Karen says some of the Northern Health School students form friendships and are very protective of each other.
"It's a rewarding job. We have a lot of contact with the families, in particular home visits, and the kids are so grateful for all that you do. The families are incredibly grateful that we can give them some normality."