This study investigates three-year-olds’ representations of the verbs think and know, in attempt to assess their understanding of factivity. Know, being factive, is used in contexts where the complement is taken to be true. Think, although non-factive, is often used in contexts where the complement also is taken to be true. Despite this, can children recognize the difference between them and understand that the truth of the complement is presupposed in only one case? Acquisition studies find that children do not have an adult-like understanding of these verbs before age four, but the tasks used are often inappropriate for testing preschoolers. We designed an interactive game to implicitly evaluate their knowledge of the verbs in a task that more directly targets factivity. Our results show that some three-year-olds are able to distinguish think and know in ways indicating they understand know presupposes the truth of its complement and think does not. The remaining three-year-olds seem to treat both verbs as non-factive. This suggests that early representations of know may be non-factive, and raises the question of how children come to distinguish the verbs.