Children often are said to pass through a series of stages in learning to represent 3-dimensional objects, such as cubes, on a 2-dimensional picture surface. Drawings of cubes from 1,734 children and adults were collected. They were classified into 10 drawing types (5 distinguished by Willats, and some additional types, one taken from Caron-Pargue). Over 80% of 5-year-olds produced a single square to represent a cube. Also, over 80% of 14- and 15-year-olds and over 80% of adults produced a parallel-projection drawing. However, there are several routes between these two milestones of drawing development, since no other drawing type captured more than 23% of the drawings at any age between 6 and 13. It is instructive that some children produced drawings that never were made by any of the adults, while some adults produced drawings of cubes that young children did not. We suggest that these differences between children and adults show that the younger children use a similarity geometry with “feature-based” criteria, while the older children and adults use a vantage-point geometry that includes “direction-based” criteria.