The drawings that 3-year-old Sally creates tend to be rather inventive and include scribbled designs that represent people, houses, cars, dogs, and so on. Which Piagetian stage/substage of cognitive development is Sally in?

symbolic function substage

Explanation:

Piaget notes a preoperational stage, where a substage called symbolic function stage corresponds to Sally:

Sally is able to represent mentally objects that are not present directly to her, she then gains ability around 2 or 4 years to do so with a inability to distinguis between her view and the view from others.

This was demonstrated as child were asked to portray view from different perspectives and they all showed : egocentrism.