Grantleigh was founded by Fred and Renette Grant on their farm at Mposa in 1996. Recognising the need for good education in the area, their intention was to develop a primary school with a rounded and balanced educational ethos.
This was an exciting phase of planning. A school name was chosen, the Loerie emblem was selected and decisions were made on colours for a school uniform, etc. Most importantly, a teacher was recruited. Showing amazing courage, Mrs Lizl Swanepoel gave up a teaching post at Kwambonambi to teach at Grantleigh.
On 21 January 1997 Grantleigh opened its doors for the first time to 16 pre-schoolers and 5 civvies-clad Grade 1 and 2 boys. Teaching took place on the Grant’s verandah and in their TV room, with swimming lessons in the family pool and cricket lessons on the tennis court.
Interest in Grantleigh was instantaneous and new learners continued to join the school. At the same time, playing fields were levelled and construction began on school buildings.
When the school opened in January 1998 there were 123 pupils, all accommodated in new classrooms. A strong contingent of Richards Bay pupils enrolled during the same year, and with them the bus transport system evolved at Grantleigh. 1998 also saw more classrooms as well as the swimming pool being built.
Grantleigh was intended to be a primary school, but pressure from parents resulted in a decision being made to phase in a secondary school component in 1999.
In 1999 there were 285 pupils enrolled, including the first Grade 8 class. This group of pupils ultimately became Grantleigh's first matric class, and they paved the way, bringing honour to themselves and the school. It was during this year that the first headmaster, Mr Peter Terry-Lloyd, the past headmaster of John Ross College in Richards Bay, was appointed to take the reins of this rapidly expanding school.
After two years the much-loved Mr Terry-Lloyd retired from years of service in the teaching profession, having made a significant contribution to Grantleigh. Mr Laurie Beadon, previously from St Dominiques in Welkom, was appointed as his successor.
The school continued to grow with each year and with it the bus fleet providing transport to and from communities to the north and south of Grantleigh.
2003 was a historic year in that for the first time Grantleigh had learners ranging from Grade R through to Grade 12. The first headboy and headgirl, Greg Rhebok and Tamaryn Whittal respectively, were appointed along with a team of prefects. This was also the year that the Grantleigh parents' association came into being under the leadership of Rev. Dudley Anderson.
April 2006 saw the departure of Mr Laurie Beadon after five years of dedicated service to Grantleigh. His successor, Mr Shaun McMurtry, joined the school from Michaelhouse in January 2007.