Year 1 · Mathematics · Measurement
Comparing length and mass
Comparing two objects directly to decide which is longer or shorter, and which feels heavier or lighter, using everyday language.
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. How we review
These lessons were written around Australian Curriculum strands and matched to UK year groups by age (Year 1 is the year a child turns 6 in England). They are not mapped to the National Curriculum in England or the curricula of Scotland, Wales or Northern Ireland, so check them against your own plans.
Learning goals
Learners will
- Compare the lengths of two objects by lining up their ends.
- Compare two objects by holding them to decide which is heavier or lighter.
- Use words such as longer, shorter, taller, heavier, lighter and the same to describe comparisons.
Success looks like
- I can line up two things at one end to see which is longer.
- I can hold two things and say which feels heavier.
- I can use words like longer, shorter, heavier and lighter.
The big idea
Before children measure with numbers, they compare things directly. This lesson is about deciding which of two objects is longer or shorter, and which is heavier or lighter.
To compare length, put the two objects side by side with their ends lined up at the same starting point, such as the edge of the table. Then look at the other end. The one that sticks out further is longer.
If the ends are not lined up, it is easy to be tricked. A short pencil pushed forward can look longer than a long pencil set further back. Always start both objects at the same line.
For things that stand up, such as people or toys, we usually say taller and shorter. Stand back to back with your child against a wall and compare heights.
To compare mass, hold one object in each hand. Which hand feels like it is being pulled down more? That object is heavier. The other is lighter.
Big things are not always heavier. A large cushion is lighter than a small tin of food. Let your child predict first, then check by holding them.
- Line up the ends to compare length.
- Hold one in each hand to compare mass.
- Bigger does not always mean heavier.
Worked examples
Which ribbon is longer?
There is a red ribbon and a blue ribbon. Which is longer?
- Lay both ribbons straight on the table.
- Line up one end of each ribbon with the edge of the table.
- Look at the other end. The red ribbon goes further.
Answer: The red ribbon is longer and the blue ribbon is shorter.
Heavier or lighter?
Which is heavier: a tin of beans or a sponge?
- Guess first: which do you think will be heavier?
- Hold the tin in one hand and the sponge in the other.
- The hand holding the tin feels pulled down more.
Answer: The tin of beans is heavier. The sponge is lighter.
Big but light
A big pillow and a small apple. Which is heavier?
- The pillow is much bigger, so it might seem heavier.
- Hold one in each hand to check.
- The apple pulls down more, even though it is smaller.
Answer: The apple is heavier, even though the pillow is bigger.
Practice check
Have a go, then check your answers. Each answer comes with an explanation.
Answer guide for parents
Two pencils are lined up at one end. The yellow pencil sticks out further at the other end. Which pencil is longer?
the yellow pencil — When the ends are lined up, the one that sticks out further is longer.
What should you do first when comparing the lengths of two spoons?
Line up their ends at the same starting point — Lining up the ends makes it fair, so you can see which one goes further.
Mum is taller than Sam. Is Sam taller or shorter than Mum?
shorter — If Mum is taller than Sam, then Sam is shorter than Mum.
You hold a book in one hand and a feather in the other. The book pulls your hand down more. Which is heavier?
the book — The object that pulls your hand down more is the heavier one.
A tin of food is heavier than a sponge. Is the sponge heavier or lighter than the tin?
lighter — If the tin is heavier, then the sponge is lighter.
Which is most likely to be heavier?
a brick — A brick is solid and heavy. A balloon and a paper cup are very light.
Is a big thing always heavier than a small thing?
No, not always — A big pillow can be lighter than a small apple. We have to hold them to check.
A shoelace and a ribbon are lined up at one end. The other ends finish at exactly the same place. Which word describes their lengths?
the same — If both ends line up at the start and at the finish, they are the same length.
Watch out for
- Comparing lengths without lining up the ends. Always start both objects from the same line, such as the edge of a table.
- Believing bigger objects are always heavier. Compare a large pillow with a small tin to show this is not true.
- Thinking a bendy or curled object is shorter. Straighten a curled ribbon next to a straight one to see its real length.
Tips for parents
- Ask your child to guess first, then check. Guessing and checking is how good measurers learn.
- Use the full sentence: 'The spoon is longer than the fork', not just 'that one'.
- Grocery unpacking is a great time to compare: which bag, tin or box is heavier?
Go further
- Make a simple balance with a coat hanger and two bags hung from it, and watch which side goes down.
- Cut a piece of string as long as your child's arm and find things in the house that are longer and shorter.
- Line up five toys from shortest to longest, then from lightest to heaviest. Is the order the same?
About 25 minutes
You'll need
- Pencils, crayons, spoons and ribbons of different lengths
- Household objects of different weights, such as an apple, a cushion, a tin of food and a sponge
- A coat hanger, two plastic bags and pegs to make a simple balance (optional)
- A flat table or floor to line things up on
Key words
- longer
- Having more length; it goes further past the other object.
- shorter
- Having less length; it does not reach as far.
- taller
- Longer from bottom to top when standing up.
- heavier
- Feels like it pulls down more on your hand.
- lighter
- Feels like it pulls down less on your hand.
- the same
- Neither one is longer or heavier than the other.
Still tricky?
For parents
Want an outside view of where your child is at?
Book a free, no-obligation English and maths assessment at a Success Tutoring centre and get a clear starting point.
Book a free assessmentRelated measurement lessons
Next steps (Year 2)