Year 1 Mathematics · AC9M1M01
Objects and events can be compared by length, mass, capacity or duration. The attribute must match the question
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Objects and events can be compared by length, mass, capacity or duration. The attribute must match the question.
Learning routine: Choose attribute → Compare fairly → Order → Explain
Use the correct comparison words for the attribute.
A fair comparison uses the same start, tool or unit.
Explain your thinking: Say what each part of the model represents, then explain why the answer or conclusion follows.
length = longer/shorter mass = heavier/lighter capacity = holds more duration = takes longer
side by side balance scale same cup same timer
Attribute sort Sort classroom questions by length, mass, capacity or duration. Model: Which is heavier? → mass
Order objects Order three pencils from shortest to longest. Model: short → medium → long
These curriculum examples extend the central model into varied contexts. They are learning contexts, not extra definitions to memorise.
using a piece of string to indirectly compare the length of several objects, deciding which will fit within a space; using comparative language to describe the order: shortest, short, longer, longest
Try and explain: A string exactly matches a shelf's length. A box is longer than that string. Will the box fit along the shelf without overhanging?
No. The string transfers the shelf's length, and the box exceeds it. Align the same starting ends when comparing.
ordering the mass of 3 or more objects such as rocks, using hefting and balance scales; using comparative language to explain the order: lightest, light, heavier, heaviest, and how they decided on the order
Try and explain: Balance scales show A heavier than B and B heavier than C. Order them from lightest to heaviest.
C, B, A. Use the mass comparisons; the biggest-looking object is not necessarily the heaviest.
pouring sand/rice/water from one container to another to compare and order the capacity of 3 or more containers; describing the order of the results in terms of which holds the most/least, and those in between
Try and explain: Three containers hold exactly two, five and three identical cups of water. Order their capacities.
Two cups, three cups, five cups: least to greatest. Using the same cup makes the comparisons meaningful.
creating sand timers from everyday items or recycled material and comparing them to order the duration of time required for the sand to run through
Try and explain: Three sand timers start together. Red empties first, blue next and green last. Which measures the longest duration?
Green. Starting together allows the finishing times to show which duration is longest.
investigating situations where First Nations Australians estimate, compare and communicate measurements; for example, the duration of seasons; understanding animal behaviour using the length of animal tracks; investigating capacity through water management techniques of First Nations Australians, such as traditional water carrying vessels and rock holes
Cultural safety: Use a community-approved source, name the specific Nation or community where the source does, and avoid presenting diverse First Nations knowledges as one generic tradition. Follow local cultural and intellectual property protocols before inviting community participation.
Compare and order objects using a named attribute and evidence.
Two shelves cannot be moved together. How could you find which is longer?
Watch for this mistake: An object can be taller yet hold less, or larger yet lighter. Decide whether you are comparing length, mass, capacity or duration.
A balance tilts down on the side with the stone. Which is heavier: the stone or the pine cone on the other side?
The heavier side moves down.
The stone is heavier.
Cup A fills 3 identical small scoops; cup B fills 5. Which has greater capacity?
Compare how much each holds using the same scoop.
Cup B. It holds more of the same-sized scoops.
Key idea: Objects and events can be compared by length, mass, capacity or duration. The attribute must match the question.
Return to the concept model if an answer is uncertain. Use the model to explain, not just to guess.
Use the Practice Sheet for written or hands-on work, Practice for supported feedback, and Test when the student is ready to demonstrate independent mastery.
Objects and events can be compared by length, mass, capacity or duration. The attribute must match the question.
Learning routine: Choose attribute → Compare fairly → Order → Explain
AC9M1M01: compare directly and indirectly and order objects and events using attributes of length, mass, capacity and duration, communicating reasoning
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