Young children are keenly aware that they are small in a world that is sized for adults. They also know that as they become older, they will become bigger in every way – taller, stronger, and able to do more things. As they look for evidence of their growth, the frequently asked question, “How tall am I?” creates an opportunity to explore the mathematical concept of measurement.
When the teachers observed the children comparing their heights in the mirror, they asked the children if they would like to measure how tall they were. Since the children often build with unit blocks, the teachers suggested that they could use small rectangle blocks as a measuring tool.
While it is natural for adults to express measurements in standard units of inches or feet, young children are not yet ready for the abstract thinking that gives those units meaning. Using nonstandard units that are familiar to children makes measurement concrete and relevant.
While it is natural for adults to express measurements in standard units of inches or feet, young children are not yet ready for the abstract thinking that gives those units meaning. Using nonstandard units that are familiar to children makes measurement concrete and relevant.
The children worked together to carefully place the blocks next to their friends, from the tip of their toes to the top of their head. Then, they counted the blocks to measure their height in rectangle block units. To make the measurements more precise, they children used a square block to equal 1/2 of a rectangle, and a square block turned vertically to indicate 1/4 of a rectangle.
Next, taping equivalent-sized paper blocks together, they each created a visual representation of their measurement to hang in the Tinker Lab. They also wrote their names and recorded their heights.
Finally, they compared their actual height with their measurements!
This experience will provide a foundation for the children to further explore the complex concept of measurement both at school and at home. For example, they might want to measure their height with other non-standard units such as Legos or markers, measure the length of everyone's shoes in their family, or compare the volume of a tall, thin glass with that of a short, wide one. Engaging in a variety of "measurable moments" will help the children construct an understanding of the mathematical language and abstract reasoning needed to answer the seemingly simple questions of, "What is the biggest?", "Is the tallest the biggest?", or "How much bigger is it?".