During the World War II Japanese occupation of Singapore between 1942 and 1945, lessons were suspended. The school opened again in 1946, a year after the Japanese surrender, once the buildings at Cairnhill and Coleman Street had been made safe following damage sustained during the war. The pre-war principal, T. W. Hinch, who had been interned by the Japanese during the occupation and had been sent back to England to recover, returned to the school in June 1946. He set up "X" and "Y" classes, each with different levels of difficulty, for students who had missed years of their education due to the occupation. In September, 1950, the secondary school relocated from Cairnhill Street to Barker Road.