Measurement
In Year 4 your child moves from simply reading measurements to converting and calculating with them. They learn to change between units such as kilometres and metres or hours and minutes, find the perimeter and area of straight-sided shapes, compare amounts of money in pounds and pence, and tell the time on both analogue and 24-hour clocks. This is the year measurement starts to join up with the rest of maths, so a confident grasp here makes word problems much easier later on.
Practise Measurement
Have a guess, even if you're not sure. Get one wrong and we'll show you why, so every miss is a chance to learn.
Timed practice
The same practice, just with a gentle clock. Pick a length and see how many you can answer.
Good to know
Units that go together
Each card shows a swap: how many small units fit inside one bigger one.
For grown-ups
Converting between units is really multiplication and division in disguise: a bigger unit always holds many smaller ones, so kilometres into metres means multiply by 1000, and metres back into kilometres means divide. The same thinking underpins perimeter, which is adding all the sides, and area, which children meet here by counting the squares inside a shape before they move on to formulas. Reading both 12- and 24-hour clocks and working in pounds and pence ties these skills to everyday situations, and the careful unit reasoning learned now is exactly what makes scaling, rates and proper area calculations feel natural in later years.
What is in this topic
- Converting between units, such as kilometres to metres and hours to minutes
- Measuring and working out the perimeter of squares and other straight-sided shapes in cm and m
- Finding the area of straight-sided shapes by counting squares
- Estimating, comparing and calculating measures, including money in pounds and pence
- Reading and converting time between analogue and digital 12- and 24-hour clocks
- Solving problems that involve converting between units of time
How to help at home
Measuring makes more sense when it happens in real moments, not just on a worksheet. A few minutes of noticing units around the house, kept practical and unhurried, builds far more confidence than a long sit-down session.
- Anchor every conversion to one swap on the card, then act it out: 1000 m = 1 km, so to turn 3 km into metres you multiply by 1000 to get 3000 m, and to turn 4500 m back into kilometres you divide by 1000 to get 4.5 km.
- Practise time in both clock styles using real timetables: half past three is 3:30 in the morning but 15:30 in the afternoon, because you add 12 to the hours once you pass midday.
- Find perimeter and area on real rectangles, like a rug or a sheet of paper. For a 5 cm by 3 cm card, add all four sides for perimeter (5 + 3 + 5 + 3 = 16 cm) and count the squares inside for area (5 rows of 3 = 15 squares).
- Turn shopping into pounds-and-pence practice: if one pencil costs 45p, ask how many you can buy with 2 pounds, working in pence (200p divided by 45p) so the units always match.
Where children get stuck
The most common slip is mixing up which way to multiply and which way to divide when changing units. A bigger unit always holds many smaller ones, so going from kilometres to metres makes the number bigger and uses multiply, while metres back to kilometres makes it smaller and uses divide. Ask 'am I making the number bigger or smaller?' before reaching for an operation, and check against the card: 2 km should clearly become 2000 m, not 0.002 m.
Children also stumble on 24-hour time, often reading 15:00 as five o'clock instead of three. The fix is to subtract 12 from any hour above 12 to find the afternoon time, so 18:00 is 6 o'clock in the evening and 21:00 is 9 o'clock at night. Naming a familiar event, like 'tea is around 17:30, so that is half past five', makes the swap stick.