Length and perimeter
Measurement
Definition
Length is an attribute related to the geometric construct of lines, and refers to how long something is. (Siemon, et al., 2015).
Students become increasingly able to recognise attributes that can be measured and how units of measure are used and calculated. In making the transition from informal to formal units, a student attends to the structure of units used to measure, how they are assembled end-to-end or side-by-side. The structure of the units give rise to ways of calculating length. (National Numeracy Learning Progression)
Teaching and learning activities
The resources below provide targeted teaching strategies to support student improvement in this skill.
Each downloadable lesson activity includes:
learning intentions
a list of required resources
a step-by-step lesson sequence
printable classroom materials
Select the download all icon to download all available activities or select each activity separately.
PLAN2 Areas of focus
An Areas of focus template has been created in PLAN2 to support targeted teaching of Text structure in your learning area.
Search for the DoE template titled ‘DoE HSCMinStd Writing: Text structure’ in the Areas of focus template library tab within the Plan menu, and customise it for your students’ needs.
For more information about using PLAN2 Areas of focus templates with this resource, visit the Using this resource with PLAN2 page.
Relevance to the numeracy test marking
According to the ACSF, the feedback for a Level 3 performance in the HSC minimum standard online numeracy test for length and perimeter states that:
Individuals performing at this level are able to “select appropriate strategies from a variety of everyday mathematical processes in familiar and some less familiar contexts. They understand and calculate familiar metric measurements for length.
Connections with ACSF Level 3 descriptors
The relevant Level 3 ACSF descriptors for numeracy are shown here to demonstrate how estimating and measuring length of linear objects and calculating perimeter is assessed in the HSC minimum standard online test. The performance features identified show what a student is able to do in order to achieve at this level and are provided to support teachers to understand what is required to achieve a Level 3 in this skill.
Numeracy Indicator 3.09: Selects and interprets mathematical information that may be partly embedded in a range of familiar, and some less familiar, tasks and texts
Focus area: Explicitness and Complexity of mathematical information
Level 3 performance features:
interprets and comprehends familiar and routine length
Numeracy Indicator 3.10: Selects from and uses a variety of developing mathematical and problem solving strategies in a range of familiar and some less familiar contexts.
Focus area: Mathematical knowledge and skills: measurement and geometry
Level 3 performance features:
measures, estimates and calculates length and perimeter
Connections with Numeracy Learning Progression
The progressions describe a typical developmental sequence of literacy and numeracy learning. The numeracy progression sub-elements, levels and indicators relevant to length and perimeter are provided here to assist teachers to identify students’ capabilities and needs to support targeted teaching.
Element: Measurement and Geometry
Sub-element: Understanding units of measurement (UuM)
UuM3 — Using informal units of measurement
measures an attribute by choosing and using multiple identical, informal units
selects the appropriate size and dimensions of an informal unit to measure and compare attributes (e.g. chooses a linear unit such as a pencil to measure length, or a square unit such as a tile to measure area)
chooses and uses appropriate uniform informal units to measure length and area without gaps or overlaps (e.g. uses the same sized paper clips to measure the length of a line; uses tiles, rather than counters to measure the area of a sheet of paper because the tiles fit together without gaps)
UuM3 — Estimating measurements
estimates the total number of uniform informal units needed to measure or compare attributes (e.g. uses a handspan or a finger width; stands an arm length apart)
checks an estimate using informal units to compare to predicted measurement
UuM4 — Repeating a single informal unit to measure
measures length using a single informal unit repeatedly (e.g. uses one paper clip to measure the length of a line, making the first unit, marking its place, then moving the paper clip along the line and repeating this process)
measures an attribute by counting the number of units used
UuM5 — Using abstract units
estimates the measurement of an attribute by visualising between known informal units (e.g. uses a cup to measure a half cup of rice; determines that about three sheets of paper would fit across a desk, and close to six might fit along it, so the area of the desk is about eighteen sheets of paper)
explains the difference between different attributes of the same shape or object (e.g. area and perimeter, mass and capacity)
UuM6 — Using formal units
measures, compares and estimates length, perimeter and area using standard metric units (e.g. I drew around my hand on centimetre grid paper and counted to find the area is about 68 square centimetres)
uses scaled instruments to measure length, mass, capacity and temperature
estimates measurements of an attribute using formal units (e.g. estimates the width of their thumb is close to a centimetre; compares capacities based on the capacity of a 600 ml bottle of water)
UuM7 — Using formal units and formula
calculates perimeter using properties of two-dimensional shapes to determine unknown lengths
UuM8 — Converting units
converts between metric units of measurement
describes the relationship between metric units of measurement and the base-ten place value system