Piaget and Child Development

After going through 3 weeks of class, I have learned and understand the different stages in Piaget’s theory and how children develop throughout each stage. For example, from birth to roughly 2 years old, children go through what Piaget would call as the sensorimotor period. Infants at this stage basically develop the very primary reactions that humans have. Then when children move on to the preoperational period, roughly 2 years old to 7 years old, they start to develop and understand more complex thoughts. Things such as symbolic representations, concepts about time and date, and simple mental imagery are being developed in this stage. After 7 years old, children move on to the concrete operations period, where complex mental representations and operations are develop. From this stage on, it is where I start to think it’s interesting. As talked about in class, children start to understand that taller container does not necessary holds more liquid in this period of life, and they start to be able to realize the conservation of number, solid, and liquid quantity. Finally, after 12 years old until the end of life, children go through the formal operations period, in which adolescent period comes in and abstract concept about the world is being developed.
Piaget’s theory about different stages and how children develop throughout these stages is definitely convincing; however, I have been thinking if this is the only explanation of how children develop? If that is so, why do some children develop faster while some develop slower? For example, when I was in elementary school, I had friends who were still figuring out the idea of conservation of matters while some friends who had already moved on to more abstract thinking. Me and my friends were in the same age, or according to Piaget, in the same development period. Then what made the difference in the speed of developing? I believe that this is an interesting question to explore on.