In 1922 Tortington Manor was converted for use as a Catholic boarding school for girls and again renamed as Tortington Park School.
Tortington Park School opened in 1922 with a small number of pupils, but was to expand to accommodate 204 girls over the coming years. Additional wings were added to the buildings in 1923, 1929 (when the estate was purchased from the Duke of Norfolk), 1933 and 1954. These buildings include a Roman Catholic Chapel which has become the Chapel House. The school bell which used to hang in the small tower on the Chapel House roof can now be seen mounted on an oak frame outside the Community Room,
The outbreak of the Second World War saw the school being evacuated to three other locations before finally returning here. The buildings of Tortington Park were requisitioned by the War Office who used the school for billeting WAAFS and other personnel based at Ford airfield or nearby Tangmere airfields. In 2009, there are still ladies living locally who remember being billeted at Tortington and when the property was redeveloped in 2000 a number of love letters to a WAAF were found hidden in the old attic rooms of the Manor House.
Tortington Park was finally handed back to the school in 1948. In 1954, the estate comprised 50 acres, with a nine hole golf course, large swimming pool, 12 tennis courts and pitches for netball and lacrosse. The buildings where South Lodge now stands housed a sanatorium with two wards, sisters' office and dispensary.
By 1969, with boarding schools becoming less fashionable, the decision was taken to close Tortington Park School at the end of the summer term. In 1970 the buildings, tennis courts, pool and twenty acres of land were sold to New England College for use as its UK campus.
Tortington Park School