The present research examines the ability of children as young as 4 years to use models in tasks that require scaling of distance along a single dimension. In Experiment 1, we found that tasks involving models are similar in difficulty to those involving maps that we studied earlier (Huttenlocher, J., Newcombe, N., & Vasilyeva, M. (1999). Spatial…

Most children who are congenitally deafblind are severely delayed in their communication development and many will not achieve symbolic understanding and expression. This article discusses developmental markers cited in the research literature as predictive of or facilitative of the development of symbolism. These markers include the growth toward…