In 1899 Marlborough Province went ahead with the idea of founding its first secondary school. Opening in 1900, Marlborough High School was at first located in the Sunday School of the All Saints’ Church in White Street. By 1901 the move to Stephenson Street had been affected and several classrooms along the south side of the Front Field were in use. Although single storey, the central entrance supported a curiously shaped bell tower. During the ‘Great Influenza Outbreak’ of 1918-19 the College closed down briefly and operated as a second hospital containing influenza wards. By the late twenties a two-storey block had been constructed at the eastern end of the original school building. This eastern wing became the Intermediate School for Blenheim (until Bohally Intermediate opened in 1956) and the western block became the recently replaced science wing.
In the mid-thirties the original single storey school was replaced with the existing two-storey old main block. There was in those days a two-storey house for the headmaster, in a small orchard, on the site of the present technical block and technical quad. The baths were completed in 1936 and subsequently had changing rooms donated in memory of the Hon. R McCallum, a Board member, who had served the school for 40 years from its inception.
In 1919 the school changed its name to Marlborough College, and thus it continued as a co-educational establishment until 1962. The community at large had lately voted in single sex education, and so, after a peak year of 1242 pupils, which made Marlborough College the third largest secondary school nationally, the Board of Governors found itself controlling the new Girls’ College on the north side of town and Marlborough College. This was renamed Marlborough Boys’ College. Each school continued with a roll of about 650 to grow to 1100 in 1980. In 1989 ‘Tomorrow’s Schools’ created an independent Board of Trustees for each College. Each school now has about 1000 students, including adult students.
In the sixties and seventies a vigorous rebuilding and renovating programme got underway. In the 1990’s a further redevelopment programme began. In 1993 the new freestanding Sir Gordon Bell Science Block opened. The John Stewart Block had extensive renovations completed in time for the 2000 Centenary. In 2003, the Goulding Sports Pavilion was completed. The new assembly hall was completed in 2004 as well as the conversion of the old Science wing into a Music Centre. In 2007, the new administration area was completed.