Museums can provide valuable benefits for children, but children from low socioeconomic (SES) backgrounds are less likely to have exposure to such institutions. We draw on interviews with 52 low-SES parents to explore how perceptions of museums influence whether parents would consider bringing their children there. Respondents express a clear preference for enriching activities for their children. However, our findings reveal a tension between this general desire and parents’ impressions of what museums are and how their children will experience them. We illustrate how limited familiarity with museums produces a circumscribed view of the range of experiences available at different kinds of museums and influences parents’ perceptions of their child-appropriateness, thus demonstrating the role of class-based cultural knowledge in shaping the choices parents make about out-of-school activities. Our findings complicate the binary narrative that attributes parental investments to either preferences or resources and highlights how cultural knowledge about such activities may contribute to social inequality. The study also offers insights for cultural institutions that wish to attract a more socioeconomically diverse base of visitors.