Best buys and exchange rates – Year 8 maths lesson

Lesson 34 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: “Is the biggest pack always the best value? When might it not be?”
Later that day or the next day: the homework (20 minutes), then a practice test.

Watch out for

Thinking the bigger pack is always better value. Work out the price per gram for each.
Multiplying when converting back the other way. Ask whether the answer should be bigger or smaller.

Tip for home: Find unit prices on shelf labels together next time you shop.

What your child will learn

We are learning to compare value for money and convert between currencies.

Success looks like

I can find a unit price.
I can decide which is the best buy.
I can convert between currencies.

Key words

best buy: the option that gives most for the money
unit price: the cost of one unit
exchange rate: how much of one currency you get for one of another
convert: change to another unit

What to have ready

Paper and a pencil
This page on a computer, tablet or phone
For the hands-on part: Compare two real pack sizes of the same food and find the price per 100 g.

The big ideas (for the adult)

To find the best buy, work out the price of one unit (per gram or per item) for each option, or the amount you get for one unit of money.

Make sure you compare the same units: change kilograms to grams if needed.

To convert money between currencies, multiply or divide by the exchange rate.

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: “use compound units such as speed, unit pricing and density to solve problems”

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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.