The school was founded in 1938. The first headmistress was Ms Marion Dickie who stayed on as headmistress until 1967. Nonsuch now holds 2 entrance examinations which must be passed in order to go to the school. This examination system was first introduced on 21st December 1937.
Awards
The school has achieved various awards such as Beacon status, Sportsmark Award, Schools Achievement Award and Education Extra - Distinction. It also gained specialist science college status in July 2004 and then language school status. This means extra funding was provided. Every year, along with St Philomena's Catholic High School for Girls, Nonsuch provides the ball girls for the Queen's Club Championships in addition to providing ballgirls for the ATP tournament. The school was awarded academy status on 1 June 2011
Selection
As Nonsuch is a grammar school, girls are required to take the 11+ exam to gain entry into year 7, which used to be a shared selection test with Wallington High School for Girls, but was made separate in 2009, and then in 2016 they were recombined. However, there are sometimes additional places in other year groups, and these are allocated based on tests in English, Mathematics and Science. There is another intake for the sixth form, which is based on GCSE results. An average points score of 50 points and a grade B or above in GCSE Mathematics and English Language is needed for this. The Nonsuch catchment area is defined by a circle with a radius of 5.25 km from the front door of the school. 80 places are awarded each year to those with the highest scores in the Entrance Test, whether they live inside or outside the catchment area. Those who pass the test and live within the circle on the cut-off date as defined by the Pan-London Co-ordinated Admissions System are ranked according to the score they achieve. Places are initially allocated according to the ranked order. If however, two or more girls have the same score and fewer places are available, the place or places will be offered to the girl or girls who live nearer to the school. The Year 7 selection test consists of two papers, Maths and English, with a short break between them. The pass mark for admission to Year 7 in 2010 was 202.
Other
In 2015, a new building project was started to expand the school and give the sixth formers more room. It is predicted to be finished in November 2015 and the furniture will be installed soon after. The school provides support for students wishing to pursue a career in Medicine, Veterinary, Oxford University or Cambridge University.
Astronomy
The school has an observatory on the roof where the astronomy society frequently meets. The school has two teachers for this GCSE. In 2008 all 5 students achieved either an A or A* grade. The Epsom and Ewell Astronomical society meet at the school observatory once a month.
