Private schools charge parents thousands, and have built themselves into a multibillion-dollar industry. Business investigations reporter Matt Nippert assesses hundreds of annual reports - sifting old money and new, and institutions run by churches and agnostic trust boards - to find out which schools have built the biggest private education empire.
Private schools charge parents tens of thousands of dollars to educate their children. Where does all that money go?
Schools in the state system have their property and costs covered by the Ministry of Education, but fully private - or part-subsidised integrated - schools are able to own their own property and have much more discretion in how to charge parents and spend the proceeds.
Most private and integrated schools are registered as charities, exempting them from income taxes, but requiring the annual filing of audited financial accounts.
Sorting education-focused charities by net assets to capture wealth, and weeding out universities and theological colleges, has allowed the Weekend Herald to rank New Zealand's 10 richest schools.
Collectively these institutions cater for nearly 12,000 children - ranging from kindergarteners to secondary students - and have more than $2b in net assets. All but one of these schools are classically private, with only one - Wesley College - operating as an integrated school with the state system.
Many operate relatively complex structures, with separate charitable entities set up to handle operations and another for capital expenditure and to wrangle donations (typically described as a "foundation"). Yet more organisations handle alumni activities and expensive extracurricular activities such as rowing and yachting. Wherever possible, these accounts have been consolidated to provide a fuller picture of the entire private school ecosystem.
Most of these schools have little or no debt, and around half the collective asset base is tied up in school grounds, with many operating large campuses on prime city real estate. The remainder of assets are held as investments, largely in real estate. One school alone, Auckland's Dilworth, owns $660m in central city properties.
Auckland, with its size and growth advantages over the past century, accounts for seven of the top 10 schools, with many clustered in the old-money suburbs of Remuera and Epsom.
The only institutions to make the cut outside the northern metropolis are Wellington's Scots College and Christchurch's Christ's College and St Andrew's College.
This methodology does bias towards older institutions, which have had time to accumulate large campuses and net asset positions, and does mean some institutions escape analysis by not having readily available financial accounts.
The schools missing from this analysis are typically those whose operations are subsumed into broader religious entities, or those run by profit-making limited liability companies such as the large ACG Schools empire operating in Auckland and Tauranga.
Despite these caveats, the sector appears remarkably concentrated. The 10 schools in these rankings seem to account for half the entire independent schools sector.
According to their annual accounts filed on the charities register, these 10 spent a combined $280m on school expenses last year. A 2015 report prepared for Independent Schools New Zealand estimated comparable spending for the sector as a whole was $450m.
1. Dilworth School, $908m in net assets
Head and shoulders above other schools in this ranking, Dilworth School is in many ways an oddity. The Epsom boys boarding school charges no fees and does no recruiting for lucrative international students. But with a net asset foundation of nearly $1 billion - underpinned by $620m in real estate investments - Dilworth has the financial resources of a mid-sized university to cater for a roll of only 603.
According to its most recent accounts, it has $17.4m cash on hand.
Founded in 1904 with a £100,000 bequest from Irish-born farmer James Dilworth ($20m in today's dollars), its trust board was given the narrow task of educating "boys from good families with limited means".
Student placements are by means-tested application only, and those accepted have their education and board entirely funded by the school's investment income.
The board has recently sought to get around their trust deed's limitation on gender by launching a $350m drive for donations to provide fresh capital to found a girls school run along similar lines.
Canny investing over the past century - its largely Auckland real estate portfolio achieved returns of 14 per cent over the past seven years - have seen it become the best-resourced secondary school in the country and its asset base per student is equivalent to Eton College, that old-money stalwart in the United Kingdom.
Partly as a result, Dilworth's teaching and administration staff are also likely to be New Zealand's best paid secondary educators. Its six key staff are said in annual reports to be receiving an average salary of $260,333.
2. King's College, $277m
Founded in 1896, King's College is in many ways the archetypal private school. It charges high fees (up to $40,750 a year for senior student boarders) for 1102 mainly (two-thirds) Pākehā students drawn from a pool where many were either born into, or became, rich-list royalty (Sir Douglas Myers, Hugh Fletcher and David Richwhite are all former students).
Its annual reports say school inventories include a stockpile of "prize ties" worth $23,257.
The vast bulk ($226m) of King's College's assets are tied up in its extensive school properties in Ōtāhuhu, which appear to be the most expensive school grounds in New Zealand. The college also holds $26m in financial investments composed of international bonds and shares.
Last year the school pulled in $6.4m in donations - on top of fees - almost half of which came from its well-heeled trustees.
While not recording exactly who gave these millions in donations, its 11-strong board includes three CEOs, three company directors, two Anglican reverends, a university professor, a legal firm partner, and is chaired by former Justice Minister, and now senior Westpac executive, Simon Power.
3. St Andrew's College, $174m
The richest school outside Auckland, Christchurch's St Andrew's was founded by Presbyterian clergy in 1917 to "educate the sons of the Presbyterian and Scottish community of Canterbury". It began accepting girls as students in 2001.
Its school buildings and land are worth $169m but suffered extensive damage - including the destruction of its chapel - during the 2011 earthquakes. They have since been rebuilt.
Until several months ago the school operated a farm - Burnett Valley, the use of which was bequeathed in 1940 - and its accounts record owning biological assets - sheep and cattle - worth $344,000. With landholdings worth $10m, since April the farm has been leased to a third party to run, with the college remaining the primary beneficiary of the trust owner.
4. Wesley College, $134m
While many private schools take pride in their production of rugby stars, only one can claim to have schooled Jonah Lomu: and that'd be Wesley College. This is an atypical school on this list in that it is integrated and its financial foundations are a mixture of Methodist and property developer.
With a largely Polynesian student body, and modest fees compared to its private peers (day schoolers are charged only $1050 for the year), its key staff are the lowest paid in these rankings, recorded as earning average salaries of $111,721.
With investment and school property landholdings totalling $115m, Wesley is the very definition of asset-rich and cash-poor. Which led the college, in 2009, to make the momentous decision to move from its grounds in Pukekohe in order to free up its substantial landholdings and generate cash through ambitious plans to build Auckland's largest housing development.
In a joint venture between the college (which provided land) and the Methodist Church (which tipped in the cash), that development, Paerata Rise, is now well-underway with the first tranche of what is hoped to be 4500 homes completed and selling, and the project now booked as an asset worth $51m on the college's books.
5. St Kentigern College, $126m
St Kentigern is the largest school in these rankings, with nearly 3000 students - nearly twice as many as the next biggest - spread across a pre-school and two primary facilities (boys and girls) in Remuera, and a secondary school split into middle and senior in Pakuranga.
The school is relatively young compared to its Auckland contemporaries, founded in only 1953, and continuing growth has seen a pile of cash - $53m all up - accumulated largely to fund ongoing building projects.
The scale of the enterprise is also reflected in senior staff salaries, with the six most senior staff - almost all principals - averaging nearly $250,000, second only to the near-$1b Dilworth.
6. Christ's College, $118m
The oldest private school in the country is the second Christchurch entry to the top 10. Christ's College is only half the size of its crosstown rival St Andrew's but has a third more net assets per student.
From its beginnings in 1850, Christ's was modelled on the upper-crust of the English public school system, with compulsory Anglican instruction until the final few years of study. The college holds $27m in investment property, $16.5m of which was flagged for sale in its most recent accounts.
Notable alumni include actor Sam Neill, the late double Victoria Cross winner Charles Upham and ANZ's New Zealand former boss, the late Sir John Anderson.
7. Diocesan School for Girls, $82m
The only girls school on this list, Diocesan is in many ways a gendered mirror of King's College: a predominantly Pākehā student population, fees for day students of $24,000, and a board stacked with legal partners, Anglican reverends, and finance executives.
Founded in 1903, the school is based - physically and financially - on its nearly $100m campus in leafy Epsom.
Investment holdings of $6.8m are likely to take a haircut in the coming months, as notes to the accounts flagged that nearly $1m had been invested with a Cayman Islands fund manager where "significant discrepancies" had been discovered and the Serious Fraud Office was now investigating.
8. Kristin School, $82m
The newest institution on this list, Kristin was founded in 1973 in what was then relatively rural Albany. Its school grounds are now recorded as worth $95m, and are home to the second-largest school on this list, with 1663 students across the entire primary-secondary range.
Kristin has more debt than its private school contemporaries - with a $11.4m mortgage across its grounds - and also owns a medical centre and a golf school that make up $4.9m in investment properties.
9. Scots College, $74m
Wellington's sole contribution to this list is Scots College, founded as a Presbyterian boys school in 1916 and which only started accepting girls this year.
While its school grounds in Strathmore Park are worth $94m, Scots has the lowest level of investments of schools in this ranking, with only $3.8m held in bonds and listed shares.
Prominent alumni include current director-general of health Ashley Bloomfield, and NBA basketball star Steven Adams. The latter, according to financial accounts, has been the school's largest donor in recent years.
10. King's School, $65m
The little brother of King's College, King's School started in 1922 when its senior sibling moved to Ōtāhuhu, which allowed a primary school to be established in its vacated Remuera premises.
Its school grounds are worth $50m, and the accounts record that it holds $10m in investments, a mixture of shares and bonds, managed by Craigs.
Curiously, artworks worth $414,300 are listed as an asset - with a revaluation claiming they appreciated in value by 8 per cent over the past year.