Erikson found sex differences in the play configurations of pre-adolescents who were given a variety of toys and blocks. Wamback, Cramer and Hogan's replications of Erikson's work revealed that sex differences of this type lack sensitivity to inter-school variation among subjects, time or locality. Two possible alternatives to Erikson's hypothesis are toy preference and spatial ability. Their influence on Erikson's task was tested with 12 year-old boys and girls from private parochial schools in the Sarasota, Florida area. After spatial aptitude was measured, the sample was divided into two groups--Replication and Plain Block. "Replication" followed Erikson's methodology exactly, and children were asked to build the scene from an exciting imaginary motion picture using a variety of toys and blocks. The second group was given the same task using only blocks. The configurations were photographed and judged for spatial function and frequency of usage of the various toys, using a revised version of Erikson's scoring system. "Replication" results generally paralleled Erikson, but several differences in the "Plain Block" condition questioned Erikson's psychosexual interpretation. Six differences had very little effect on block building in any dependent variable categories. The presence of some factors posited to be social-cultural in nature, other than those originally discussed by Erikson, seemed most significant. Data were interpreted as consistent with Erikson's psychosocial theory and discussed from this perspective. (Author)