More and more Auckland parents are opting to spend thousands of dollars sending their children to boarding school - even if they live just minutes away.

King's College headmaster Bradley Fenner said parents were happy to pay the extra $8000 a year to save driving to and from school and sporting activities, and to know their child was living in a supervised, structured environment. The King's hostel, which has beds for 400 students, has had a 39 per cent increase in boarders from the local region since 2002.

Year 13 student William Steel, 17, has been boarding since he started at the college in Otahuhu even though he lives in Remuera.

It would take him no more than half an hour to get to school by train, but William prefers no commute at all.

He is involved in rugby, swimming and tennis and loves the convenience of going to practice on-site, just a few minutes' walk from his bedroom.

He has also found the nightly two hours of obligatory study, or "prep", has helped his schoolwork as it is easy to do it when everyone is around him.

William's mother, Charlotte Steel, said modern technology allowed the family to keep up-to-date through regular text messages, and they enjoyed having him home at weekends.

William has two younger sisters who have sporting activities almost daily, Ms Steel said, so his decision to board had eased pressure on the family's evenings.

"Boarding depends entirely on the child. For us it's been a positive decision."

Mr Fenner said King's College students were "spending so much time here that it actually makes it easier if they live on site".

St Cuthbert's College principal Lynda Reid said the school had noticed a definite trend in local families looking to board in recent years.

"Families who live in what would have been considered 'easy commuting distance' in the past - people who live in Karaka [near Papakura] or on the North Shore - started becoming interested in boarding."

Student involvement in extra-curricular activities was increasing and 92 per cent of the senior school participated in sports, Mrs Reid said.

Because of the way sports games were run on several days of the week, students no longer had to pick just one summer and one winter sport they could play badminton on Wednesday, hockey on Thursday and netball on Saturday morning, she said.

"If a girl was the sort of student who was involved in two or three sports and a couple of cultural activities, [boarding does] make a difference," Mrs Reid said.

Mt Albert Grammar headmaster Dale Burden said there was growing demand for boarding from Aucklanders who lived out of zone but wanted their son to be a "MAGS boy".

The idea of monitored homework was a huge drawcard for parents.

Mt Albert's boarding fee was $9000 - but there were no tuition fees on top of this, Mr Burden said.

Epsom Girls Grammar School and Auckland Grammar School said they took boarders only from outside Auckland.