Describes two experiments that assessed young children's understanding of the characteristic uncertainty in the physical nature of random phenomena as well as the unpredictability of outcomes. (HOD)

Examined the longitudinal predictability of spatial ability in late-adolescent females. No timing of puberty or lateralization effects were observed. These findings strengthen evidence that sex-related differences in spatial ability could be experientially determined and may help to focus the search for exactly how this occurs. (Author/GLR)