In 1924, Junior House and the Clock Tower were constructed. 1941 saw the Senior Cup Team (SCT) win the Colleges' first Leinster Schools Rugby Senior Cup, trained by Fr Leahy, OP. In 1950, the Junior Cup Team (JCT) won the schools first Leinster Schools Junior Cup Final. Building began for Senior House in 1951. In 1952 the College marked its centenary, events to celebrate the milestone were attended by the President of Ireland Seán T. O'Kelly, Taoiseach Éamon de Valera, the Papal Nuncio, the Master of the Dominican Order and the Bishop of Kildare and Leighlin.