Kindergartners, second, and fifth graders made repeated trips through a large- or small-scale model town, and then constructed from memory the layout of buildings in either a large- or small-scale space. Accuracy of construction increased as a function of developmental level and repeated trips through the town. Children's constructions were most accurate when they were tested in the same-scale environment as that in which they developed their spatial knowledge; accuracy was impaired significantly only when children were exposed to a small space and then reconstructed in a large space. Results were interpreted in terms of a "competence-load trade-off."