GM3-1: Use linear scales and whole numbers of metric units for length, area, volume and capacity, weight (mass), angle, temperature, and time.

Elaboration on this Achievement Objective

This means students will recognise that length, area, volume and capacity, weight, angle, and temperature are the characteristics (attributes) of objects people most commonly measure in everyday life. Time is a special attribute since it is not tangibly attached to physical objects. Measurement involves quantifying an attribute using units. Units of measure have characteristics including being a part of the attribute they measure and uniformity (same size). When measuring, the units need to fill a length, space, time etc., with no gaps or overlaps (this is known as tiling). At Level Three, students should be familiar with common units in the metric system for the attributes listed. These units include metres, centimetres, millimetres, and kilometres for length/distance, square and cubic centimetres, and metres for area and volume, kilograms and grams for weight, quarter and half turns for angles, degrees Celsius for temperature, and seconds, minutes, hours, days, etc for time. It is not expected that students will know the size relationships between measures though they should have opportunities to explore these relationships, for example 15cm = 150mm. Using measurement instruments involves reading linear scales (an analogue clock face is three connected linear scales). Students should understand that the marks on a linear scale show the endpoint of units and that scales always have a baseline (zero). Part of measurement is selecting the scale, with the precision of unit, suitable for a task. Level Three students should apply their additive and multiplicative number strategies to measurement problems that involve whole numbers of units, for example how many cubic centimetres will fit in this packet?