Measurement for young children is really about the idea of comparison. Is the red pipe cleaner longer than the green one? Which carrot is the longest? The shortest? This is really an exercise in evaluation and estimation – important real worlds skills. Using rulers may be an important skill, but being able to judge length, weight, volume, size, etc. is developed through experiences with matching and comparing objects. Children also need to practice using the tools of measurement such as scales, cups, thermometers, and rulers. But don’t rush for those rulers too soon. Young children benefit from “non-standard units” of measure. An “inch” is a very abstract concept – but measuring with unifix cubes, blocks, body parts, or whatever is easily available and familiar is more meaningful and teaches the big idea that objects can be represented by units of measurement.