Young children's responses to a velocity inference task based on static pictorial stimuli giving cues of proximity and ratio were examined. Subjects (N=65) in preschool through second grade viewed pictures of snails moving horizontally or spiders suspended vertically and were asked to estimate which competitor would reach its destination first. Cues on the diagrams included proximity of competitor to destination and distance already traveled. Easy diagrams had all other factors constant; difficult diagrams (including manipulated starting points and distances traveled) were solved correctly only if proper ratio calculations were made. Preliminary analylses showed no sex differences nor any effect of test order. Main effects of orientation (horizontal or vertical) and age-orientation interaction were not found, but a highly significant main effect of task difficulty (qualified by a significant age/task difficulty interaction) was revealed. Although older children develop strategies for velocity estimation, these skills do not result in correct judgments in all contexts. (DH)