Age and sex differences in children's spatial search strategies.

Male and female children, 3, 4, and 5 years old, searched for a sticker that was hidden in 1 of 15 linearly aligned boxes. Two identical bear-shaped landmarks cued the sticker location, which was always in the middle of 3 boxes that separated the two landmarks. The absolute locations of the landmarks and sticker varied across training trials, but the distance in relation to each other remained constant. Training continued until the child chose the correct box first for 3 consecutive trials or for a maximum of 20 trials. Striking age and sex differences emerged in acquisition: The percentage of children who reached criterion increased over age groups to 100% for the boys but stayed at approximately 20% for the girls. A landmark expansion test (with the landmarks moved farther apart) given to children who met criterion revealed that most of these children chose the middle location.