Piaget studied children's performance on a variety of problems, including the three-mountains problem and the class-inclusion problem. Choose either the three-mountains problem or the class-inclusion problem

Describe the features of the problem, give an example of how a child in the preoperational period might solve the problem, and discuss how Piaget interpreted preoperational children's performance on the problem.

What will be an ideal response?

In the three-mountains problem, an experimenter places a model of three mountains of different sizes on a table in front of child. The child's goal is to identify which view of the mountains people sitting at different points around the table would see. Preoperational children tend to say that another person at the table would see the same view as they do, regardless of the person's position at the table. Piaget interpreted children's performance as evidence of their egocentrism. In the class-inclusion problem, an experimenter presents children with a set of objects that can either be grouped together as superset (e.g., 7 checkers), or be separated into two subsets (e.g., 5 blue checkers and 2 red checkers). The children's goal is to say whether there are more objects in the larger subset (e.g., 5 blue checkers) or more objects in the superset (7 checkers). Preoperational children tend to say that there are more objects in the larger subset than in the superset. Piaget interpreted children's performance as evidence of their tendency to focus on a single dimension to the exclusion of others.