collyer's ceased to accept boarders in 1935, and the dormitories were converted into much-needed library and common-room space. plans for adding a gymnasium and other facilities were abandoned in 1939, when the school accepted evacuees from the mercers’ school in london, and pupil numbers soared to over 400 in three streams. (the accommodation crisis was solved by building hutted classrooms, but numbers continued to rise because of the post-war ‘baby boom’, and the huts were not demolished until the 1980s.) in 1944 it became a voluntary-aided grammar school, and its education was again made available free to the scholars. in the 1950s it had around 500 pupils, rising slowly to over 600 during the 1960s.