Preoperational stage: Lack of Conservation
Developmental psychologist Jean Piaget divided human mental development into stages through the lifespan with emphasis on the early years of life (Myers, 2014). He proposed that from approximately age two to seven, children function in a Preoperational stage; that is they are unable to intentionally manipulate perceptions in their minds to make sense of the world (Myers, 2014). As a result they can be more easily deceived by their perceptions than older children and adults. Specifically, Piaget determined that children of this age group lack the concept of conservation or possess an inability to understand that quantities remain constant even when they change shape (Myers, 2014). This limitation in thought development has key implications for teachers of students under the age of seven.
Piaget demonstrated that lack of conservation in the Preoperational stage of development was universal regardless of the quantities tested (Dewey, 2011). In a classic experiment, he placed two identical glasses of the same quantity of liquid in front of a child. He then took one of these glasses and poured the contents into a taller, thinner glass while the child watched carefully. He then asked the child which glass contained more liquid; the taller thin glass or the shorter glass. Children subjected to this test always selected the taller glass as having more liquid. Generally speaking they were unable to separate shape from quantity in their minds (Myers, 2014). Similarly, children at this stage of development were unable to differentiate objects of the same mass that have been molded into different shapes. Piaget demonstrated this when he showed children two equal balls of clay. He stretched one into a longer sausage shape and asked a child to select which had more clay in it. The child selected the longer, sausage shaped clay. Piaget demonstrated the same result with tests for area and for numbers of objects such as coins spread-out into various shapes (Dewey, 2011).
A young child’s relative inability to mentally “preserve something in the face of change” (Dewey, 2011, paragraph 9), is important for teachers of children aged two to seven for two reasons. First, activities or lessons which require children of this age to conserve quantities in their minds while shapes or other elements of a substance change may not be productive. Children at this stage of development simply cannot consistently perform this mental operation. Second, teachers need to be aware that some children will develop conservation sooner than others (Myers, 2014). This should not be misinterpreted as higher functioning or higher intelligence in these children. In fact, children between the ages of two and seven who show differing abilities in conservation are simply showing typical differences along the normal developmental timeline (Myers, 2014). Only by the age of seven, should teachers begin to expect that nearly all of their students will possess mental conservation ability. Teachers should use this knowledge to develop their curriculum accordingly.
References
Dewey, Russell A. (2011). The Conservation Experiments. Retrieved from http://www.intropsych.com/ch10_development /conservation_experiments.html
Myers, David G. (2014). Psychology (10th ed.). New York, NY: Worth
Publishers
Piaget demonstrated that lack of conservation in the Preoperational stage of development was universal regardless of the quantities tested (Dewey, 2011). In a classic experiment, he placed two identical glasses of the same quantity of liquid in front of a child. He then took one of these glasses and poured the contents into a taller, thinner glass while the child watched carefully. He then asked the child which glass contained more liquid; the taller thin glass or the shorter glass. Children subjected to this test always selected the taller glass as having more liquid. Generally speaking they were unable to separate shape from quantity in their minds (Myers, 2014). Similarly, children at this stage of development were unable to differentiate objects of the same mass that have been molded into different shapes. Piaget demonstrated this when he showed children two equal balls of clay. He stretched one into a longer sausage shape and asked a child to select which had more clay in it. The child selected the longer, sausage shaped clay. Piaget demonstrated the same result with tests for area and for numbers of objects such as coins spread-out into various shapes (Dewey, 2011).
A young child’s relative inability to mentally “preserve something in the face of change” (Dewey, 2011, paragraph 9), is important for teachers of children aged two to seven for two reasons. First, activities or lessons which require children of this age to conserve quantities in their minds while shapes or other elements of a substance change may not be productive. Children at this stage of development simply cannot consistently perform this mental operation. Second, teachers need to be aware that some children will develop conservation sooner than others (Myers, 2014). This should not be misinterpreted as higher functioning or higher intelligence in these children. In fact, children between the ages of two and seven who show differing abilities in conservation are simply showing typical differences along the normal developmental timeline (Myers, 2014). Only by the age of seven, should teachers begin to expect that nearly all of their students will possess mental conservation ability. Teachers should use this knowledge to develop their curriculum accordingly.
References
Dewey, Russell A. (2011). The Conservation Experiments. Retrieved from http://www.intropsych.com/ch10_development /conservation_experiments.html
Myers, David G. (2014). Psychology (10th ed.). New York, NY: Worth
Publishers