This article examines how participants enrolled in teacher education and childhood studies courses represented their understandings of childhood through a selection of artefacts discussed in focus groups at four sites: Montréal, New York City, Ottawa, and Toronto. To situate our inquiry, we theorise nostalgia in relationship to the construction of childhood innocence, with a focus on children's everyday objects and playthings in upholding this ideal. We further trace the construction of innocence to discourses of social exclusion and defences against difficulty. While participants used their artefacts to represent personal memories and social contexts that disrupted an idealised category of childhood, they also returned to a nostalgic trope of innocence, which was particularly pronounced in their understandings of childhood under COVID-19. We advocate for the creation of time and space for prospective and practicing teachers to mourn the idealisation of innocence and to examine the unequal conditions of vulnerability that both children and teachers live.