This paper approaches the question of Spinoza and education via the work of Louis Althusser. One important aim is to show how Spinoza’s description of the imagination underpins Althusser’s description of the ideological ‘infrastructure’ of educational practices and institutions. To achieve this, I begin by addressing Spinoza’s treatment of the physiological foundation of the imagination: by showing that the realm of ‘individual consciousness’ is more like the effect of an anonymous field, or process, Spinoza, we see, becomes a kind of immanent cause for the Althusserian claim that ‘ideology has a material existence’. I go on to examine, in detail, Althusser’s description of ‘educational apparatuses’, locating these as the expressions of a Spinozistic ontology. However, Althusserian anti-humanism can also appear to negate transformative agency; and in the specific context of the classroom, Althusser suggests, apparently ‘heroic’ teachers seem almost doomed. Hence a ‘return’ to Spinoza, enacted, here—that is, an examination of Spinozistic potentialities, mainly adumbrated in the unfinished Political Treatise. My article concludes by suggesting that, in light of these, the foundational unit of pedagogical practice—the group, the class—might still be reconfigured as a collective subject, rather than the mere object of ideology.