On 2 September 1947, Sisters Pauline, Roger and Melissa came to St Cuthbert's. Sister Pauline left in 1948 for Canada and was succeeded by Sister M Luke until July 1949 when Sister Teresita took charge with Sisters Roger and Enda as assistants.

There were 67 children on roll when the Marist Sisters took charge. In 1956 the school was reorganised and became a primary school. The senior children transferred to the new Catholic Secondary School of St Thomas the Apostle in Chertsey. Sister M Kevin was appointed Headmistress to succeed Sister Teresita. Sister Teresita, Sisters Bernard, Enda and Amelia were on the staff. Sister Berenice later replaced Sister Amelia.