223 It is therefore Our urgent desire that this doctrine be studied more and more. First of all it should be taught as part of the daily curriculum in Catholic schools of every kind, particularly seminaries, although We are not unaware that in some of these latter institutions, this has been done for a long time now and in an outstanding way. We would also like to see it added to the religious instruction programs of parishes and of Association of the Lay Apostolate. It must be spread by every modern means at our disposal: daily newspapers, periodicals, popular and scientific publications, radio and television.
Source: Mater et Magistra (Vatican.va)