Measurement conventions Standard units like inches exist as the result of discussions and agreements among people about measurement problems. 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. Iteration Measurement means repeated application of identical units. Children's Thinking about Length Primary grade children usually have some knowledge of units of measurement.
Children can use unconventional items like paper clips to measure lengths.
Using such materials to solve measurement problems requires that children consider the meaning of a measurement unit. Asking children to solve problems about the measurement of length emphasizes inventive thinking rather than rote use of rulers. Children need to learn that identical units must be used when measuring. They usually need experiences working on and discussing measurement problems to understand why identical units are necessary. We have observed teams of children happily mixing adult and child shoes of different sizes to measure the length of a classroom.