Sarah Clark has been living with arthritis for 10 years - and she's only 32.
Miss Clark, the sports co-ordinator at Golden Sands School, was diagnosed with rheumatoid arthritis after she began getting joint pain mirrored on both hands 10 years ago.
The school is holding a fundraising mufti day on Miss Clark's behalf today to raise money for Arthritis New Zealand. Most of the 340 children will wear orange and be given Arthritis New Zealand merchandise.
Miss Clark said it would come as a surprise to some of the parents that she had arthritis because it was unusual to see the disease in someone so young.
About 530,000 people in New Zealand suffer from arthritis and about 1000 of those are young.
After she was diagnosed, Miss Clark said it took four years of trialling medication before an effective one was found. Until then, she had trouble walking and was in a lot of pain.
"I moved here in 2011 and it's been going great since then. The new drug really helped me get my life back, the treatment has been really successful."
When going through diagnosis and treatment, she discovered a lack of support services for young people who had the disease so, with a friend's help, started her own support group.
The Super Young Arthritics of New Zealand group now has more than 700 members who meet in different parts of the country.
"Newly diagnosed people just want contact with other people who understand what you're going through. Arthritis is usually pretty invisible unless you have a big lump or something like that.
"The people who originally joined the group were in their 20s. You feel you've missed a big chunk of your life, you can't do some things people our age do. Even going out for dinner is hard."
Miss Clark is also a volunteer for Arthritis New Zealand and will be attending one of its youth camps this year to act as a mentor.
Rheumatoid arthritis
*An inflammatory illness that affects the joints and because it is "systemic", it can affect other parts of the body.
*It is a chronic disease that lasts a lifetime, however people often experience periods of remission when the disease subsides.
*There is no cure but there are effective treatments available resulting in lower pain and fewer disabilities.
- Arthritis New Zealand