Prisons for Minors (PM) are relatively new in the French prison landscape correctional system. Their appearance reflected a political desire to turn incarceration spaces for youths aged 13 to 18 into properly “educational” spaces, in order to address the lack of socio-educational attention thatminor prisoners were suffering in juvenile units in adult prisons. Based on a monographic study conducted within two PMs, combining direct observation of everyday prison life and semi-structured interviews with all PMactors, this contribution aims to analyse the form taken by educational practices in these establishments, and examine how they are weaved into the penitentiary order. After providing some context relating to the juvenile justice system in France, we will examine the practices of PJJ tutors (Protection judiciaire de la jeunesse / Youth Judicial Protection Service) in symmetry with those of prison guards. This symmetrical analysis will lead us to show that, although PMs testify to a decompartmentalisation in relation to the prison institution, they are still marked by the dominance of security rationales over educational rationales. This dominance also testifies to an original connection between these two rationales: in PMs, it is not solely a matter of forcing the bodies of prisoners to submit to the penitentiary order; it is also an effort to enlist cloistered subjectivities through an “educational” work of persuasion concerning the validity of the penitentiary order.