11+ maths metric units practice
21 October 2026
Why metric units matter
Understanding metric units is a key part of 11+ maths. Children need to recognise, compare and convert units like millimetres, centimetres, metres and kilometres. These skills appear in questions on measurement, perimeter, area and word problems.
Common metric units in 11+ maths
The most common metric units your child will see are:
Millimetres (mm)
Centimetres (cm)
Metres (m)
Kilometres (km)
Grams (g)
Kilograms (kg)
Millilitres (ml)
Litres (l)
Learning the relationships between these units helps children spot the right conversion quickly.
Worked example
Converting centimetres to metres
Question: A piece of string is 250 cm long. How many metres is this?
Step 1: Recall that 1 metre = 100 centimetres.
Step 2: Divide the number of centimetres by 100.
250 ÷ 100 = 2.5
The correct answer is 2.5 metres.
Key insight: Encourage your child to write down the conversion they are using each time. This helps them avoid simple errors and builds confidence.
Practical tips for home practice
Ask your child to measure objects around the house and convert the measurements between different metric units. Use rulers, measuring jugs and kitchen scales to make practice hands-on and meaningful.
Building confidence with conversions
Start with simple conversions, such as centimetres to metres or grams to kilograms. Once your child is confident, introduce more complex problems that combine different units or require more than one step.
