Minimum core obligations are the obligations on the State to ensure the satisfaction of minimum essential levels of a right. Vis-à-vis the right to education this includes: prohibiting discrimination in access to and in education, ensuring free and compulsory primary education for all, respecting the liberty of parents to choose schools for their children other than those established by public authorities, and protecting the liberty of individuals and bodies to establish and direct educational institutions.
Minimum core obligations are not subject to progressive realisation, however: “In order for a State Party to be able to attribute its failure to meet at least its minimum core obligations to a lack of available resources it must demonstrate that every effort has been made to use all resources that are at its disposition in an effort to satisfy, as a matter of priority, those minimum obligations” (Committee on Economic, Socail and Cultural Rights (2003) General Comment 3: The Nature of States Parties’ Obligations (Art. 2, Para. 1): Para.10).
For further information on the minimum core obligations of the right to education, see Coomans, F (1998) Clarifying the Core Content of the Right to Education.