Gravissimum Educationis is the Second Vatican Council’s Declaration on Christian Education. It was promulgated on 28 October 1965 by Pope Paul VI, following approval by the assembled bishops by a vote of 2,290 to 35.
You will find on this link the Gravissimum Educationis Declaration
Sapientia Christiana is an apostolic constitution issued by Pope John Paul II on April 15, 1979. Sapientia Christiana is the canonical, academic law governing "ecclesiastical" post-secondary education.
You will find on this link the Sapientia Christiana Constitution
Ex Corde Ecclesiae (From the Heart of the Church) is an apostolic constitution issued by Pope John Paul II regarding Catholic colleges and universities. Promulgated on 15 August 1990 and intended to become effective in the academic year starting in 1991, its aim was to define and refine the Catholicism of Catholic institutions of higher education. Institutions newly claiming to be Catholic would require affirmation from "the Holy See, by an Episcopal Conference or another Assembly of Catholic hierarchy, or by a diocesan bishop".
You will find on this link the Ex Corde Ecclesiae Constitution
Pope Francis promulgated the Apostolic Constitution on Monday, January 29, 2018. Entitled Veritatis Gaudium , the "joy of truth", it concerns universities and ecclesiastical faculties. In this text of about 60 pages, the Pope invites these educational structures to adapt to contemporary cultural changes, in keeping with the missionary transformation of an "outgoing" Church.
You will find on this link the Veritatis Gaudium Constitution