Although a great deal of research has focused on ontological judgments in preschoolers, very little has examined ontological judgments in older children. The present study asked 10-year-olds and adults (N = 94) to judge the reality status of known real, known imagined, and novel entities presented in simple and elaborate contexts and to explain their judgments. Although judgments were generally apt, participants were more likely to endorse imagined and novel entities when the entities were presented in elaborate contexts. When asked to explain their reasoning, participants at both ages cited firsthand experience for real entities and general knowledge for imagined entities. For novel entities, participants referred most to indirect experiences when entities were presented in simple contexts and to general knowledge when those entities were presented in elaborate contexts. These results suggest that rich contextual information continues to be an important influence on ontological judgments past the preschool years.