[3] In 1624 and in memory of his son Henry who died that same year, Sir William decided to build a "free school" in the town in order "to teach twenty-four poor children to write, read and cast accounts, such as their parents and friends are not able to maintain at school".

Boys entered the school between the ages of ten and fourteen and at the end of two years, six of the best were given two pounds each to apprentice themselves to a trade.

The school office and reprographics room is housed in the original flint building, which was unveiled in 1624.

In the late 1980s a new sports gym was added, followed in 1992 by new modern languages facilities and library in a new building facing onto West Street.

As a result of this building work, other space within the school was adjusted with a rolling programme, and a new style eatery called "Mimi's Café" was added, along with a new Sixth Form Centre.

At the beginning of the 2006 Autumn term, the headmaster announced that the Library was to be renamed the "Learning Centre".

[8] The Sir William Borlase's Grammar School Boat Club has had members reaching international events.