The trustees of the Barrow Trust became the new school's governors, and they began organising a suitable sum of money to allow the project to go ahead.

The school formally opened in October 1878, with just twenty-three pupils (nine of them from the village of Borden) and one full-time member of staff (the headmaster, Rev.

Thurnham left to establish New College, Herne Bay in 1906, and took most of the 120 boarders and the majority of the school's staff with him, leaving the next headmaster, William Murdock, with the difficult task of building up numbers once more.

The new building was formally opened by George, Lord Harris in October 1929, but the school retained its original name despite no longer being located in Borden.

The original pavilion was replaced by a modern structure in 2004, which continues to serve as a memorial to all those old boys who were killed in the First World War.

Meanwhile, air raid shelters were built on the east side of the school site in Sittingbourne and, later, to the north of the cricket pavilion.

[5] The word 'Grammar' was removed from the school's name in 1972, in accordance with a change in the local education system, and there were fears that Borden might be turned into a Sixth Form college.

The first phase of another new teaching block, the Short Block (named for the school's sixth headmaster, Bryan Short), was opened in 1995 and completed in 1998; the finished building was formally opened by Robin, Lord Kingsdown, the great-grandson of the school's first chairman of governors, Sir Edward Leigh Pemberton.

With this status and an associated increase in funding, the school has built many new facilities, including a multi use games area (MUGA) and the William Barrow Library.

The school's badge, which in heraldic terms is blazoned as 'azure, a chevron or between three crescents of the last', is believed to have been derived from the coat of arms of William Barrow; however, no proof of this connection has been uncovered, despite extensive efforts in the 1930s.

This replaced an earlier school song, which began with the words 'Borden, you merit all our praise, Our home through countless happy days.'

In 1931, a brick-and-timber sports pavilion was constructed and dedicated to the fallen Old Bordenians of the First World War; this was replaced by a modern brick building, which was rededicated in 2004.

In 2011, the OBA funded two war memorials that record the names of all those Old Bordenians who fell in armed conflict in the Twentieth Century.

Since then, wooden plaques have been placed over the entrances to individual classrooms within the School and commemorate the names of the Old Bordenians killed in the First World War.

The school's first cadet corps was formed in 1903, affiliated to 4th Volunteer Battalion, The Queen's Own (Royal West Kent Regiment) and commanded by one of the masters.

The Cadet Corps was removed from the Army List in 1906, following the transfer of the headmaster, James Thurnham, and most of the school's staff and boarders, to New College, Herne Bay.