In the early nineteenth century, the ideas of reform pedagogues gave rise to a didactic turn towards the visual that criticised an exclusive textual mediation of knowledge through books and lectures. To raise educational effectualness, teachers came under increasing pressure to incorporate high-profile media technologies into their lessons. Yet, top-down initiatives to implement new instructional technology often fell short of expectations when logistical and financial challenges and teachers' practices and preferences were not taken into account. However, most of the existing studies on the introduction and proliferation of high-profile educational technology in late nineteenth- and early twentieth-century Western education have focused on industry-led promotional efforts or governmental initiatives to introduce commercially produced media into the classroom. As such, they lend insight into the normative discourse surrounding the construction of the ideal of the tech-savvy teacher, but have mostly overlooked teachers' agency, as well as the difficulties teachers met in the implementation. This paper investigates how, between 1900 and 1940, Belgian secondary school teachers dealt with the tension between professional pressures and expectations on the one hand, and their individual preferences and possibilities on the other hand. It does so by comparing the discourse of educational media advocates and governmental actors with teachers' accounts of their visual media practices as documented in teachers' pre-class preparations and notes.