Mr Scott said short courses were on offer but an ongoing approach was preferable. Such an approach helped cement the skills women and girls needed to protect themselves.
"They develop self-confidence."
The regular 90-minute evening sessions run twice a week at the Otumoetai College gymnasium.
The death of Mrs Gotingco has shocked her North Shore community in Auckland.
Responding to the crime, Mile High Karate North Shore has invited women and their daughters to a free personal safety course this week to learn techniques to defend themselves.
Owner Paul Bryant said the school was "taking a stand" to help mothers, wives, partners and daughters not become victims.
"Sadly, there are too many news stories about women being abducted or assaulted and beaten, or worse."
He said attacks on women were terrifying and potentially life changing, but with the right knowledge and basic skills, women could escape and help others.
While devices such as pepper spray and tasers are outlawed in New Zealand for personal use, some self defence instructors encourage women to use perfumes and aerosols - which can have a similarly painful effect - in their place.
Coalition for the Safety of Women and Children spokeswoman Leonie Morris said self-defence classes were just one tool in the fight against violence towards women.
She said the biggest problem was our culture, which perpetuated outdated and sexist ideas about women.
"What we really need is men to stop being violent towards women. To achieve that, we need to challenge the many misogynist ideas which underpin that violence."
Outdated ideas like it was OK for men to have power and control over women were still prevalent, Ms Morris said.