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Children are fascinated with transformation. You can see this in their play, in which they are transforming the world physically as well as symbolically. We construct an understanding of things by changing them and, when possible, changing them back. There are many ways of thinking about transformation. In this chapter, I will consider transformation as a big idea, as an umbrella that subsumes all the kinds of transformation that make up the physical and social world that children must understand and construct.
In order to look carefully at this big idea, 1am first going to describe the different kinds of transformation. Once we have considered the different types of transformation, you will be able to look at what you can do to help children make connections and to see the relationships among all kinds of transformation.
Movement of Objects
The first kind of transformation we will look at has to do with the movement of objects. The position of objects and materials can be changed by moving them. Balls can be rolled, pendulums can be swung, water can flow, and air can blow. Children construct a great deal of physical knowledge by moving objects. The construction of this physical knowledge is best described by Constance Kamii and Rheta Devries in their classic book Physical Knowledge in Preschool Education (1978). In this book, they describe numerous ways that you can encourage the construction of physical knowledge by providing children with activities and experiences that allow them to experiment with the physical world. This means that the children have opportunities to act on objects and materials, to vary their actions, and to see the results of their actions. In The Young Child as Scientist (Chaillé & Britain, 2003) we build on the work of Kamii and Devries by describing a curriculum model for early childhood science education based on children's questions, and the question appropriate for this type of transformation is "How can I (we) make it move?" While this is a great science-oriented question, the way to think of this as a big idea is to think of the movement of objects as just one component of transformation.
For the purposes of delineating a big idea, I find that one of the key differences between the different kinds of movement as well as the different kinds of transformation is whether or not they are reversible or irreversible.
Reversible Movement
I'll start with a focused and specific idea to make reversible movement clear. Reversible movement---or "back and forth"----can be illustrated by pendulums.
Children’s experimentation with pendulums is rich with possibility because all of the variables children can control------the weight of the bob, the length of the string, the strength of the swing, and the size and weight of the target hit by the bob. And things that swing are common in the child's world, on the playground and in the environment. Back and forth also implies a much bigger notion, that of reversibility----what goes in one direction comes back in the opposite direction; what goes up comes down; that which is changed can be returned to its former state. So while I am going begin with the idea of pendulums, keep in mind that this is to just the start. We will be extending this to be a bigger concept that of reversible transformation.
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Micki and Vangie have set up tower made out of cardboard blocks to serve as a target for their pendulum game. Micki is standing with the pendulum bob in her hand------ a bob made out of a plastic bottle------- and is calling out instructions to Vangie. "Put one more block on top!" Vangie adds another block, and then Micki walks the pendulum with the bob over to the construction and tests out the swing to see if it will hit the target. Returning to her original place, she lets the bob go, and it swings toward the target, missing it by only a couple of inches. The girls laugh, and then Micki catches it when it swings back and quickly releases it again, changing her aim lightly. When it hits the target, it bounces off the cardboard blocks. Vangie says, "Let's use this one,” and gets another plastic bottle that is filled with sand, "It's heavier" They fasten the new, heavier bottle onto the rope and try again. The block structure collapses.
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