After receiving his doctoral degree at age 22, Jean Piaget began a career that would have a profound impact on both psychology and education. Through his work with Alfred Binet. Piaget developed an interest in the intellectual development of children. Based upon his observations, he concluded that children are not less intelligent than adults, they simply think differently. Albert Einstein called Piaget's discovery "so simple only a genius could have thought of it." Piaget created a theory of cognitive development that described the basic stages that children go through as they mentally mature. He believed that children are like "little scientists," actively trying to make sense of the world rather than simply soaking up information passively.
One of the key concepts in Piaget's theory is the use of schemas. According to Piaget, schemas are cognitive frameworks or concepts that help people organize and interpret information. As experiences happen, this new information is used to modify, add to or completely change previously existing schemas. For example, a young girl may have a schema about a type of animal, such as a cat. According to her schema, cats are furry and have four legs. When she first encounters a dog, she might initially believe that the animal is a cat. Once the she learns that this is actually a dog, she will revise her schema for cats and create a new category for dogs.