24 Regarding the individual defense of children and youths, We know, from reports which reach Us from all over the world, that activity in the ranks of Catholic Action constitutes the best protection against the strategems of evil, the most efficacious training ground in Christian strength. These youths, enraptured with the beauty of the Christian ideal, sustained by the Divine Help which is assured by prayer and the Sacraments, will dedicate themselves with ardor and joy to the conquest of the souls of their companions, gathering consoling harvests of good.
Source: Nos Es Muy Conocida (Vatican.va)