Gnostic groups have often been spoken of as ‘schools’. In particular, this has been common with regard to groups that appear to have been centred around a teacher, such as Valentinus and Basilides. But how pertinent is the comparison with philosophical schools? The paper will take a fresh look at the evidence for teaching activities in Valentinianism as far as the existence of such activities may be inferred from the sources themselves. Did classroom teaching exist as a separate activity in addition to religious services and rituals? Were the contents and methods of teaching comparable to those of the philosophical schools? It will be argued that teaching in the form of exegesis, theoretical exposition and diatribe was indeed practiced in Valentinian circles, but the Valentinian teachers did not see themselves as philosophers and important differences vis-à-vis philosophical teaching must be pointed out.