In 1898 Grant, who was interested in co-education, was appointed the first headmaster of the newly reopened Keswick School. Along with Bedales School the school was the first co-educational day/boarding school in England. After a number of years, difficulties with the local authority and lack of a chapel prompted a move. The Harpenden site was discovered by one of the masters, a new limited company formed and Grant together with 59 boys and girls and many of the staff moved there. The new school where pupils "could live in an atmosphere closely related to family life, based on sound Christian principles" was officially opened in 21 June 1907.