# Measurement of Length

Children's thinking about measuring length is the topic of this newsletter. Measurement problems, like arithmetic problems, are basic to daily experience and arise in many different situations. It is important for children to have opportunities to learn more about measurement. They learn through thinking about measurement problems. Knowing about how children tend to think about measurement helps adults to guide children's discovery of the principles of measurement.

If children are simply told to measure length in a unit like an inch, they develop very little understanding of the principles of measurement. Children need the opportunity to understand principles about measurement. These principles include:

1. Appropriate units
Use units of measure appropriate to the thing being measured. Units that work for measuring the length of your driveway may not work for measuring the length of your notebook. Units used to measure length may not serve well for the measurement of area.

2. Identical units
To say that a candy bar is 5 inches long means that every inch is exactly the same.

3. Measurement conventions
Standard units like inches exist as the result of discussions and agreements among people about measurement problems. The "foot" we use today comes from the length of a certain king's foot. People in his kingdom adopted this as a standard that has been passed on. When children participate in the process of forming conventions, they come to see their utility.

4. Iteration
Measurement means repeated application of identical units.