This research examines the extent to which specific forms of historical representation in Northern Ireland and the United States serve as “cultural tools” that shape understanding of change over time. On the basis of classroom observations and interviews with children in Northern Ireland, and using comparisons with previous U.S. research, this study found that children in the two locations differed in their explanations of how and why social and material life has changed over time. These distinctions correspond to differing historical representations; children in Northern Ireland are less likely, for both political and pedagogical reasons, to encounter the kinds of national narratives common in the United States. These findings suggest that educators should consider how reliance on a single format for presenting historical information influences and limits children’s historical thinking.