The first Principal, Mr A.T. Gibson, emphasised 'manners, character, scholarship and human relations'.

The school developed a tradition of 'self-help' and through much fundraising has built up some very good facilities for the use of the students and staff.

Facilities such as the Swimming Pool (1962), the Gymnasium (1968), the Centre Court, the extensions to the Cafeteria and Theatrette (1980's), the Shelters (1990's), The Department/Ministry of Education has added the Library (1970), The Music Block (1972), Te Atawhai (1996), Music and Drama renovations (1999), Staffroom – Te Arahi (1999), Science Block and Deans' House – Te Whare Kaiārahi (2002), and new Gymnasium facilities (2006).

[9] In Years 11 to 13, students work towards the National Certificate of Educational Achievement (NCEA) the main secondary school qualification in New Zealand,[10] and international qualifications such as Cambridge Assessment International Education in Mathematics.

[11] The school has had eight principals in its history:[12] The official Houses Opening Day for all students and staff of Whanganui High School took place on Friday 16 February 2018 at the Jubilee Stadium, Whanganui.

Those names were gifted to the school, along with the iwi story of the origin of the Whanganui River[13] at the Houses Opening Day.

Confucius Institutes are non-profit public institutions aligned with China that aim to promote Chinese language and culture, support local Chinese teaching internationally and organise student cultural exchanges.