 As a schoolteacher specializing with delinquent and other troubled children, Barker was appointed principal of the London County Council's Women's Institute correctional facility in 1913.After serving for two years, Barker resigned from her post to join Britain's war effort during World War I, teaching army cooks and as lady superintendent of the Royal Arsenal, Woolwich, overseeing its 30,000 female workers.Following the war, Barker joined the Ministry of Labour's training department and, in 1923, was appointed governor of the Borstal Institution for Girls at Aylesbury.