Final answer:
Children in the age range of 2-6 years are in the Preoperational stage, where they use symbols but lack the ability to apply logical reasoning and understand conservation.
Step-by-step explanation:
Children between 2-6 years identify and use symbols for objects but do not have the ability to apply logical reasoning during the Preoperational stage of Piaget's theory of cognitive development. This stage spans approximately from 2 to 7 years old. During this time, children engage in pretend play and use language to represent words, images, and ideas. However, they cannot yet understand adult logic or mentally manipulate information. An example of this is a child thinking they have more of something, like pieces of pizza, even when the quantity is the same but just divided differently. They lack the understanding of conservation, the concept that the quantity remains the same despite changes in form or appearance.