U.S. National Standards
4.1. Understand measurable attributes of objects and the units, systems, and processes of measurement.
4.1.1. Recognize the attributes of length, volume, weight, area, and time.
4.1.3. Understand how to measure using nonstandard and standard units.
4.1.4. Select an appropriate unit and tool for the attribute being measured.
4.2. Apply appropriate techniques, tools, and formulas to determine measurements.
4.2.3. Use tools to measure.