Maria Elise Marchant was born on 28 October 1869 at Wellington, New Zealand, the daughter of Maria Elise Wright and her husband, John William Allman Marchant, a surveyor who later became surveyor general and secretary for Crown lands. John Marchant's original surname was Allman: his mother had remarried and he had adopted his stepfather's name.
Maria Marchant was educated at the Greenwood Sisters' Terrace School and at Wellington Girls' High School, where she was known as Ella. She was dux of the school in 1887. Having set her sights firmly on a teaching career, Marchant taught at Mary Anne Swainson's Fitzherbert Terrace School in 1888 and 1889 and at Wellington Girls' High School from 1890 to 1895. Although in full-time employment, she studied extramurally through Canterbury College and graduated BA in 1892 and MA in 1894.
In 1895 Maria Marchant was appointed lady principal of Otago Girls' High School. She was selected on the casting vote of the chairman of the board of governors from a strong field of 39 applicants. Marchant differed from her two predecessors who were both Scots, in that she was New Zealand-born and -educated. She took up her position on 21 December 1895 at an annual salary of £400 plus free accommodation at the school.
Maria Marchant set a high standard for both her staff and pupils. She was an admired figurehead for the school: always composed and well dressed, she was an accomplished public speaker and debater and a woman of considerable intellectual bearing. She was widely read and took a lively interest in current events and travel. On Saturday evenings the boarders would gather in her sitting room sewing while she read to them, usually from Dickens. After an extensive overseas trip in 1901, she also entertained them with accounts of her travels.
Marchant's years as school principal were not without difficulty. She was not easily intimidated by or deferential towards authority, which frequently brought her into conflict with the board of governors. On a number of occasions, more often in her earlier years as principal, the board voted to defer any consideration of her proposals for school reform. It took 12 years to persuade the board to appoint a teacher for commercial subjects. Classes in cooking, singing, swimming and dressmaking were introduced by 1903 and art classes were compulsory for all girls up to the sixth form but shorthand, bookkeeping and typing were not established until 1908.
Marchant ensured that the girls' physical welfare was not overlooked. A highly successful annual sports day was launched and teams regularly played tennis, hockey and basketball. Her other accomplishments included successfully lobbying for a new school building, the re-establishment of the school magazine in 1910 and the revival of the Ex-High School Girls' Association. Throughout her 16-year principalship she consistently voiced ideas that were at variance with conventional educational wisdom. She believed, for instance, that the recommendation of teachers, rather than examination results, should determine a pupil's progress through the school and entrance to university.
At the end of 1911 Maria Marchant resigned from Otago Girls' High School. A devout Anglican, she had for many years been interested in establishing an Anglican teaching order in New Zealand. She now travelled to England to investigate the different charitable, educational and religious organisations run by the Church of England. On returning to New Zealand she lived in Auckland where, in 1914, she was superintendent of the Anglican Children's Home at Ponsonby. In February 1915 she became the founding headmistress of the Church School for Girls (later St Mary's Diocesan School) Stratford. She visited England again during 1916 and resigned from St Mary's at the end of the first term in 1917 to set up Bishopscourt, Christchurch, as a hostel for women students; she was in charge of the hostel until 1918. Her hope that some of the students would form the nucleus of a teaching order for Anglican schools was not realised.
During 1917 Maria Marchant had assisted in the founding of the school which became St John's Girls' School, Invercargill. She was acting headmistress when she died suddenly of a cerebral haemorrhage on 15 November 1919. She had just turned 50 and was about to return to Dunedin to establish the religious community and teaching order she had planned for so long. Maria Marchant had never married. She was buried in the family plot at Karori cemetery, Wellington.