This article explores the hidden gendered curriculum concealed in the texts, exhibitions and other structural devices of museums and what they teach visitors to see and think. Grounded in conceptualisations of culture, representation, and language, past feminist studies of museums and applying feminist visual discourse analysis (FVDA) we found hiding in plain sight in public museums in Canada and England a diversity of 'languages' that subversively aggrandised masculine power and privilege and (re)inscribed negative or limited understandings to women which we argue as feminist adult educators have epistemic, identity and agency consequences. We also argue that whilst museums are trying to address often centuries old exclusionary gendered practices progress is slow because these practices are so embedded and unconscious and reflect pervasive social notions of 'common sense'. Our study makes an important contribution to feminist museum studies by rendering visible a web of complex structural and textual gendered biases and to adult education. By adding museums to our curricula we can provide our students with a visual and immersive way to hone the critical visual literacy skills needed to understand more fully how both seen and unseen languages operate not just in the museum, but across society.