Clarendon High School for Girls is a semi-private English medium high school for girls situated in the suburb of Selborne of East London in the Eastern Cape province of South Africa.

In 1905, a new uniform was introduced, consisting of a navy gym with green and white colours on the blazers and hats.

In 1937, the upper grades were moved to new premises on the corner of Connaught Avenue and Oxford Street, and the lower grades remained as a separate school.

In 1964 the school hostel, Connaught House, was destroyed by fire.

[2] Miss Donald, headmistress from 1925 to 1945, introduced the prefect system in 1933 and in 1934 appointed the first headgirl, Betty Chew, who was later a teacher at the school and coached the first hockey team until the 1980s.