Year 2 · Mathematics · Measurement
Measuring length with informal units
Measuring and comparing the lengths of objects by laying equal-sized units, such as paperclips or blocks, end to end with no gaps or overlaps.
Awaiting educator review. This material was drafted by our content team with AI assistance and is waiting for review by a qualified educator. Please check it suits your child before using it. Created 10 October 2026.
These lessons were written around Australian Curriculum strands and matched to New Zealand year levels by age (NZ Year 1 is the first year of school). They are not yet mapped to The New Zealand Curriculum, so check them against your own learning programme.
Learning goals
Learners will
- Measure length by placing identical units end to end.
- Compare and order objects using their measurements.
- Explain why units must be the same size and have no gaps or overlaps.
Success looks like
- I can line up units end to end with no gaps or overlaps.
- I can say how many units long something is.
- I can use my measurements to say which object is longer or shorter.
The big idea
When we measure length, we find out how many units fit along an object. A unit can be anything that is all the same size: paperclips, blocks, hand spans or footsteps.
Units must go end to end in a straight line, with no gaps and no overlaps. If there are gaps, we count too few; if units overlap, we count too many.
Start the first unit exactly at the end of the object. Keep adding units until you reach the other end, then count them. If the last unit goes a little past the end, we can say 'about 7 paperclips' or 'just over 6 paperclips'.
Measurements let us compare objects that cannot sit side by side. If the spoon is 5 blocks long and the fork is 3 blocks long, the spoon is longer by 2 blocks.
The size of the unit matters. A ribbon might be 4 big blocks long but 8 small blocks long. Smaller units mean we need more of them, so when comparing, we must use the same unit every time.
Before measuring, ask your child to estimate. Guessing first, then checking, builds a sense of how long things really are.
Worked examples
Measuring a pencil
How many paperclips long is a pencil?
- Lay the pencil on the table.
- Put the first paperclip so its end lines up with the end of the pencil.
- Add paperclips one after another, touching, in a straight line.
- Stop at the other end of the pencil and count the paperclips: 6.
Answer: The pencil is 6 paperclips long.
Comparing two shoes
A child's shoe is 9 counters long. Dad's shoe is 14 counters long. How much longer is Dad's shoe?
- Both shoes were measured with the same unit, so we can compare.
- 14 is more than 9, so Dad's shoe is longer.
- Count on from 9 to 14: 10, 11, 12, 13, 14. That is 5.
Answer: Dad's shoe is 5 counters longer.
Practice check
Have a go, then check your answers. Each answer comes with an explanation.
Answer guide for parents
A pencil is 6 paperclips long. A crayon is 4 paperclips long. Which is longer?
the pencil — 6 paperclips is more than 4 paperclips, so the pencil is longer.
A spoon is 5 blocks long. A fork is 3 blocks long. How many blocks longer is the spoon?
2 — 5 − 3 = 2, so the spoon is 2 blocks longer.
Why should there be no gaps between paperclips when you measure?
Gaps make you count too few paperclips — Gaps leave parts of the object unmeasured, so the count is too small.
A book is 7 hand spans long. A table is 12 hand spans long. Which is longer, the book or the table?
table — 12 hand spans is more than 7 hand spans, so the table is longer.
Which unit would be best for measuring the length of a hallway?
footsteps — A hallway is long, so a bigger unit like footsteps is quicker and easier.
Sam measures a ribbon with big blocks and gets 4. Mia measures the same ribbon with small blocks. What will Mia get?
more than 4 — Smaller units mean more of them are needed to cover the same length.
A scarf is 15 blocks long. A sock is 8 blocks long. How many blocks longer is the scarf?
7 — Count on from 8 to 15: 9, 10, 11, 12, 13, 14, 15. That is 7 blocks, so 15 − 8 = 7.
A toy worm is 3 pegs long, a toy snake is 10 pegs long and a ribbon is 6 pegs long. Which is the shortest?
the toy worm — 3 is the smallest number of pegs, so the toy worm is the shortest.
Watch out for
- Leaving gaps or overlapping units. Model careful placement and ask your child to check each join.
- Not lining up the first unit with the end of the object. Point to the starting edge every time.
- Comparing measurements made with different units. Show that a ribbon can be '4' or '8' depending on block size.
Tips for parents
- Always ask for an estimate first, then celebrate close guesses rather than exact ones.
- Use the phrase 'about' when the units do not fit exactly — real measuring is rarely perfect.
- Let your child choose what to measure; curiosity keeps them engaged.
Go further
- Measure family members' feet with blocks and order everyone from shortest to longest foot.
- Cut a piece of string the same length as your child's height and find things in the house that are longer or shorter.
- Measure a garden path in footsteps, then ask an adult to measure it in their footsteps. Talk about why the answers differ.