Understand the idea.
Choose the right comparison
First ask what you want to compare. Length is how long; mass is how heavy; capacity is how much fits inside. The question tells you which feature to investigate.
Choose a method that measures that feature. Use a row of equal blocks for length, a balance for mass, or repeated equal cupfuls for capacity. Colour alone cannot answer any of these measuring questions.
Keep the comparison fair
A fair comparison keeps the measuring method the same. For lengths, match starting ends and use equal blocks touching in a row. For capacity, use the same cup filled to the same level.
Check the method before trusting the count. Four blocks with gaps do not measure four blocks of length fairly: some of the row is empty space. Fix the arrangement, then measure again.
See the method in action.
Fix the blocks
Four blocks have gaps between them under a pencil. Is that a fair length measure?
Worked solution
- 1
Look between the blocks.
The row has gaps, so some of its length is not covered by blocks.
- 2
Close the gaps and match the start.
Equal blocks must touch end to end to make a fair measuring row.
- 3
Check the far end and count again.
The new row must match the pencil length before its block count can be used.
No. The row needs equal touching units.
Choose a tool
You want to know which lunchbox is heavier. Should you compare their colours or use a balance?
Worked solution
- 1
Name the feature in the question.
Heavier asks about mass.
- 2
Choose a balance.
A balance shows which lunchbox makes its pan lower.
- 3
Explain why colour does not help.
A lunchbox colour does not tell us how heavy it is.
Use a balance.
Try it yourself.
Check your understanding
Two containers are measured with different-sized cups. How could you make the comparison fair?
Show answer & reasoning
Measure both again with the same cup.
Measure both containers again with the same cup, filled equally each time. Equal units make the two counts describe comparable amounts.
Keep practising
6 worksheet questions
Read the questions online
- You want the longest ribbon. What should you line up first?
- You want the lighter toy. Which tool helps: a balance or a small cup?
- You want the container that holds most. Which unit helps: equal cupfuls or pencil lengths?
- Use the picture. Which row measures fairly, A or B? Explain.
- A block row overlaps at two places. What must you fix?
- A child says a tall empty bottle holds more than a short wide bottle just because it is taller. What would you suggest?
Read the worked solutions
- You want the longest ribbon. What should you line up first?
Use a shared starting point.
One end of each ribbon. - You want the lighter toy. Which tool helps: a balance or a small cup?
Lighter describes mass.
A balance. - You want the container that holds most. Which unit helps: equal cupfuls or pencil lengths?
Cupfuls compare capacity.
Equal cupfuls. - Use the picture. Which row measures fairly, A or B? Explain.
Row A has equal units without gaps.
Row B leaves gaps between the blocks.
A. The equal blocks touch end to end. - A block row overlaps at two places. What must you fix?
Each unit should cover a new part of the length.
Place the blocks end to end without overlaps. - A child says a tall empty bottle holds more than a short wide bottle just because it is taller. What would you suggest?
Height alone does not show the total capacity.
Check by filling each with the same cup, or compare by careful pouring.
Curriculum reference & lesson scope
Australian Curriculum v9 / SA Curriculum 2026
Year 1 informal comparisons and measuring with uniform units; explanation and practical activity accompany fluency.
Official curriculum source ↗