There are many theories used to describe how children develop over their lifespan. Stage theories are those that are organized into distinct changes in development, or leaps, which help us understand growth and provide us with guidance on when to expect changes in learning or skills. These theories often align with age based expectations and milestones. We mentioned earlier that theories can become outdated due to cultural shifts and new research findings. Because of this, we do not include many of the typical developmental theories present in other textbooks.

For example, students or instructors who have studied psychology or human development in the past might be surprised that we do not feature Sigmund Freud and his research. While we recognize that parts of Freud’s work were used by other theorists featured in this textbook, we simply do not find his theories relevant in describing child development in today’s society. Lastly, we will include common criticisms of each theory. Theories are helpful, but we recognize that they are not always inclusive or free from bias.

Theory of Cognitive Development

Featured in Chapter 5, Chapter 7, Chapter 10, Chapter 13.

Jean Piaget (1896–1980) is one of the most influential cognitive theorists. Piaget was inspired to explore children’s ability to think and reason by watching his own children’s development. He was one of the first to recognize and map out the ways in which children’s thought differs from that of adults. His interest in this area began when he was asked to test the IQ of children and began to notice that there was a pattern in their wrong answers. He believed that children’s intellectual skills change over time through maturation. Children of differing ages interpret the world differently.

Piaget believed our desire to understand the world comes from a need for cognitive equilibrium. This is an agreement or balance between what we sense in the outside world and what we know in our minds. If we experience something that we cannot understand, we try to restore the balance either by changing our thoughts or by altering the experience to fit into what we do understand. Perhaps you meet someone who is very different from anyone you know. How do you make sense of this person? You might use them to establish a new category of people in your mind, or you might think about how they are similar to someone else.

Schemas are categories of knowledge. They are like mental boxes of concepts. A child has to learn many concepts. They may have a schema for “under” and “soft” or “running” and “sour.” All of these are schemas. Our efforts to understand the world around us lead us to develop new schemas and modify old ones.

One way to make sense of new experiences is to focus on how they are similar to what we already know. This is assimilation. So the person we meet who is very different may be understood as being “sort of like my brother” or “his voice sounds a lot like yours.” Or a new food may be assimilated when we determine that it tastes like chicken!

Another way to make sense of the world is to change our minds. We can make a cognitive accommodation to this new experience by adding a new schema. For instance, when you try a new food and think, “This food is unlike anything I’ve tasted before. I now have a new category of foods that are bitter-sweet in flavor,” you are engaging in accommodation. Children accommodate more frequently as they build new schemas. In contrast, adults tend to look for similarities in their experiences and assimilate. They may be less inclined to think “outside the box.”

Piaget suggested different ways of understanding that are associated with maturation. He divided this into four stages (Figure 2.1).

Criticisms of Piaget’s Theory

Although Piaget’s theory has made significant contributions to the science of child development, Piaget has been criticized for overemphasizing the role that physical maturation plays in cognitive development and for underestimating the role that culture and interaction (or experience) play in cognitive development. Looking across cultures reveals considerable variation in what children are able to do at different ages. Piaget may have underestimated what children are capable of given the right circumstances.

Piaget’s theory of cognitive development suggests that cognitive development is complete by the age of 12. However, most recent research demonstrates that this developmental period of adolescence is one of important cognitive increases. Another main criticism of Piaget is his methodological approach, especially with regard to his use of his own children in his observations and his cultural bias.

Psychosocial Theory

Featured in Chapter 6 and Chapter 8.

In his theory of psychosocial development, Erik Erikson (1902–1994) suggested that our relationships and society’s expectations motivate much of our behavior. Erikson was a student of Freud, but he emphasized the importance of the ego, or conscious thought, in determining our actions. In other words, he believed that we are not driven by unconscious urges. We know what motivates us and consciously think about how to achieve our goals. He is considered the father of developmental psychology because his model gives us a guideline for the entire life span and suggests certain primary psychological and social concerns throughout life.

Erikson expanded on Freud’s theory by emphasizing the importance of culture in parenting practices and motivations and adding three stages of adult development (Erikson, 1950; 1968). He believed that we are aware of what motivates us throughout life and that the ego has greater importance in guiding our actions than the id. We make conscious choices in life, and these choices focus on meeting certain social and cultural needs rather than purely biological ones. Humans are motivated, for instance, by the need to feel that the world is a trustworthy place, that we are capable individuals, that we can contribute to society, and that we have lived a meaningful life. These are all psychosocial problems.

Erikson divided the lifespan into eight stages (figure 2.2). In each stage, we have a major psychosocial task to accomplish or a crisis to overcome. Erikson believed that our personality continues to take shape throughout our lifespan as we face these challenges.

Criticisms of Erikson’s Theory

These eight stages form a foundation for discussions on emotional and social development during a lifespan. However, these stages or crises can occur more than once. For instance, a person may struggle with a lack of trust after infancy under certain circumstances. Erikson’s theory has been criticized for focusing so heavily on stages and assuming that the completion of one stage is a prerequisite for the next crisis of development. His theory also focuses on social expectations that exist in certain cultures but not in all. For instance, the idea that adolescence is a time of searching for identity might translate well in the middle-class culture of the United States but not as well in cultures where the transition into adulthood coincides with puberty through rites of passage and where adult roles offer fewer choices.

Kohlberg’s Stages of Moral Development

Featured in Chapter 5, Chapter 7, Chapter 11, Chapter 13.

Lawrence Kohlberg (1927-1987) was an American psychologist who was interested in learning about moral reasoning throughout the lifespan. He was influenced by Piaget’s ideas on cognitive development, specifically the way in which an individual reasons and thinks. Kohlberg was less interested in how reinforcement influenced behavior, which was a popular view during his time, and instead wanted to learn more about how an individual forms moral ideas that influence their decision making.

Kohlberg studied his ideas by analyzing how children respond to moral dilemmas. He interviewed boys ages 10, 13, and 16 and taped their responses, leading to his creation of the six stages of moral development (Kohlberg, 1963). Kohlberg organized these stages into three levels of moral reasoning, coinciding with age progression and advances in cognitive thinking (Figure 2.3).

The Heinz dilemma is one of Kohlberg’s most well known dilemmas and consists of a person responding to the question “Should the husband have done that?” (Kohlberg, 1969).

A woman was near death from a special kind of cancer. There was one drug that the doctors thought might save her. It was a form of radium that a druggist in the same town had recently discovered. The drug was expensive to make but the druggist was charging ten times what the drug cost him to make. He paid $200 for the radium and charged $2,000 for a small dose of the drug. The sick woman’s husband, Heinz, went to everyone he knew to borrow the money but he could only get together about $1,000, about half of what the drug cost. He told the druggist that his wife was dying and asked him to sell it cheaper or let him pay later. But the druggist said: “No, I discovered the drug and I’m going to make money from it.” Heinz got desperate and broke into the man’s store to steal the drug for his wife.

Criticisms of Kohlberg’s Theory

The biggest criticism of Kohlberg’s work concerns the lack of female subjects and inclusivity. Kohlberg only tested male subjects, and he presumed that only males could achieve higher levels of moral development and that women would get stuck at stage 3 due to their focus on relationships and nurturance (Waller, 2005). Kohlberg’s stages were also reviewed for cultural inclusivity. It was noted that while similarities exist across cultures regarding moral reasoning in the earlier stages, this was not the case in the later stages, most likely due to significant cultural differences in ideas of respect, truth, and other moral values (Gibbs et al., 2007).

Licenses and Attributions for Stage Theories

“Stage Theories” by Christina Belli is licensed under CC BY 4.0.

“Theory of Cognitive Development” by Christina Belli is adapted from “Child Growth and Development” by Jennifer Paris, Antoinette Ricardo, & Dawn Rymond is licensed under CC BY 4.0.

“Psychosocial Theory” by Christina Belli is adapted from Psychosocial Theory by Lumen Learning which is licensed under CC BY 4.0.

Figure 2.1. Jean Piaget’s Theory of Cognitive Development adapted from Child Growth and Development, by Jennifer Paris, Antoinette Ricardo, & Dawn Rymond is licensed under CC BY 4.0.

Figure 2.2. Erik Erikson’s Psychosocial Theory adapted from Erikson’s Psychosocial Stages of Development, Child Growth and Development by Jennifer Paris, Antoinette Ricardo, & Dawn Rymond is licensed under CC BY 4.0.

Figure 2.3. Lawrence Kohlberg’s Levels of Moral Reasoning Using the Heinz Dilemma table adapted from “Child Growth and Development” by Jennifer Paris, Antoinette Ricardo, & Dawn Rymond is licensed under CC BY 4.0.