Units and measures – Year 8 maths lesson

Lesson 9 of 35 in the Year 8 maths course

UK version. UK school years, UK spelling and pounds (£). · US Math Department

A complete 45-minute lesson for Year 8 (ages 12–13) that runs on this page – at school or at home. Every answer is marked straight away, with a worked explanation.

Time: 45 minutes + 20 min homework
Year: Year 8 (ages 12–13)
You need: Paper, a pencil and this page
Marked: Instantly, with explanations

For parents: how to use this lesson

You don't need to know this topic yourself. The lesson explains each step on screen, one tidy step at a time. Every answer is marked straight away with a worked explanation, so you never have to mark anything.

Read what your child will learn and the big ideas together.
Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
Let them do the practice on their own. They choose Getting started, On track or Challenge – start on On track and move up after a few right in a row.
Finish with the exit ticket and the talk question: “Why is 1 m² equal to 10,000 cm² and not 100 cm²?”
Later that day or the next day: the homework (20 minutes), then a practice test.

Watch out for

Using 100 for square centimetres in a square metre. Draw the square: 100 cm by 100 cm is 10,000 cm².
Dividing when converting to a smaller unit. More of a smaller unit: multiply.

Tip for home: Convert recipe amounts or road distances between units.

What your child will learn

We are learning to convert between units of length, area, volume, time and money.

Success looks like

I can convert lengths, masses and capacities.
I can convert areas and volumes.
I can convert between metric and imperial units.

Key words

convert: change to another unit
metric: units based on powers of 10
imperial: older units such as inches, feet and miles
conversion factor: the number you multiply by

What to have ready

Paper and a pencil
This page on a computer, tablet or phone
For the hands-on part: Measure a table in centimetres and metres and work out its area in both units.

The big ideas (for the adult)

Use the conversion fact as a multiplier: 1 inch ≈ 2.54 cm, so 10 inches ≈ 25.4 cm.

For area, square the length conversion: 1 m² = 100 × 100 = 10,000 cm². For volume, cube it: 1 m³ = 1,000,000 cm³.

Ask whether the answer should be bigger or smaller: converting to a smaller unit gives a bigger number.

The lesson, step by step

45 minutes in 5 parts
Part	Time	How it is checked
Starter: quick recall	5 min	Marked by Classfern
Teaching input	10 min	Not assessed, self-checked
Worked examples and guided practice	9 min	Not assessed, marked by Classfern
Independent practice	15 min	Marked by Classfern
Plenary and exit ticket	6 min	Marked by Classfern, self-checked

Starter, "your turn", practice and exit ticket are marked by Classfern. Worked examples and teaching are not assessed. The hands-on task and the reflection are self-assessed. Explanations in talk are judged by the parent and not recorded.

The lesson

It runs here on the page. No sign-up and no names – progress is kept only in this browser.

Homework and practice at home

20 minutes: 10 practice questions, 3 multiple-choice questions and 2 to remember from earlier work, then a short reflection. New questions every time, all marked instantly.

More practice

All Year 8 maths lessons and tests · Maths Department

More Year 8 maths lessons

Curriculum

National Curriculum for England, Year 8: “use standard units of mass, length, time, money and other measures, including with decimal quantities”

National Curriculum for England, Year 8: “change freely between related standard units [for example time, length, area, volume/capacity, mass]”

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Our lessons and questions are our own. They are not written or endorsed by any government department, testing agency or exam board.