Measurement
In Year 6, measurement becomes about choosing the right step rather than learning brand new facts. Children convert between metric units with growing confidence, including answers that run to three decimal places, and use the rough link between miles and kilometres to swap between the two. They also work out the area of triangles and parallelograms and the volume of a cuboid, and solve problems that bring several measures together.
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
Much of this year is about formulas and the reasoning behind them: a triangle is exactly half its surrounding rectangle, and the volume of a box is its length times its width times its height. Converting between units leans on the same place value work children are doing elsewhere, so the strands of maths start to join up. This is the groundwork for the area, volume and unit conversion that run all the way through secondary school, where the shapes get harder but the underlying habit, deciding what you are changing and which way it goes, stays exactly the same.
What is in this topic
- Converting metric units, including answers to three decimal places
- Converting between miles and kilometres
- Perimeter and area of composite shapes
- Area of triangles and parallelograms
- Volume of cuboids using the formula, and comparing volumes
- Money and measure problems
How to help at home
Measurement at this stage is less about new facts and more about choosing the right step, so the most useful thing you can do is slow the first move down. Before any sum, ask "what am I changing, and which way does it go?" That one habit prevents most of the slips.
- When converting units, decide the direction first, then multiply or divide. Going to a smaller unit means more of them, so 2.5 m becomes 2.5 x 100 = 250 cm; going to a bigger unit means fewer, so 4500 g becomes 4500 / 1000 = 4.5 kg.
- Break a composite shape into rectangles and add the parts. For an L-shape made of a 6 cm by 2 cm strip and a 3 cm by 4 cm block, work out 6 x 2 = 12 and 3 x 4 = 12, then add for an area of 24 square cm.
- Practise the triangle rule as 'rectangle, then halve'. A triangle with base 8 cm and height 5 cm gives 8 x 5 = 40, halved to 20 square cm, because a triangle is exactly half its surrounding rectangle.
- For the rough miles-to-kilometres link, use 5 miles is about 8 km. So 15 miles is three lots of 5, which is three lots of 8, giving roughly 24 km.
Where children get stuck
The most common wobble is converting the wrong way, turning 250 cm into 25000 m by multiplying when they should divide. Anchor it to the size of the unit: a metre is bigger than a centimetre, so a length needs fewer metres than centimetres, which means dividing by 100. Saying 'bigger unit, smaller number' out loud before writing anything usually catches the slip.
The other frequent mistake is forgetting to halve when finding the area of a triangle, so they report the whole rectangle instead. Picture the triangle sitting inside its rectangle and remind them it fills exactly half: base times height gives the rectangle, and the final answer is always that figure divided by two.