Cover lesson · PSE / Well-being · Year 7 · Beginner
LNF: Numeracy → Understanding the number system helps us to represent and compare relationships between numbers and quantities → Calculation
Name: Class: Date:
Print: this sheet, one per pupil, and the stimulus sheet “Drinks label cards”, one between two. No computers are needed. Pupils need a calculator for Steps 3 to 6, but not for Step 2.
Run: 5 min pupils read the stimulus in pairs · 5 min Step 2, estimating without a calculator · 12 min Step 3, sugar in one serving · 8 min Step 4, a day of drinks · 10 min Step 5, swaps over a week · 7 min Step 6, traffic light colours · 8 min Step 7, writing advice alone. Total 55 minutes.
Collect: this sheet. It is numeracy practice in calculation: pupils estimate, multiply and divide decimals, find percentages, convert grams to teaspoons and add up totals over a day and a week, with their working shown in the tables. It supports well-being by showing how quickly sugar adds up in drinks. The drinks and Cai are invented; the 30 g daily limit and the label colours are real NHS and UK government guidance. Pupils are not asked what they eat or drink, and nothing on the sheet is about body weight or shape, so please keep any class discussion that way too.
A drink label tells you how much sugar is in 100 ml, but you probably drink more or less than 100 ml. You will use calculations to find the real amount of sugar in a serving, turn it into teaspoons and a percentage of the daily limit, and work out which swaps save the most sugar over a week.
Read the whole stimulus sheet with a partner, including the boxes at the bottom. Find the daily limit of free sugars for someone your age.
Round the numbers to make them easy, then estimate the sugar in one serving. The first one is done for you.
| Drink | Round the numbers and estimate | Estimate |
|---|---|---|
| F: Ras Sports Drink, 500 ml | 4 g in each 100 ml, and 500 ml is 5 lots of 100 ml: 4 × 5 | about 20 g |
| A: Ffizz Cola, 330 ml | ||
| B: Mellt Energy, 250 ml | ||
| C: Haul Orange Juice, 150 ml | ||
| D: Llaeth Mefus Strawberry Milk, 330 ml |
(a) Which drink on the cards has the most sugar per 100 ml?
(b) Which drink do you predict has the most sugar in one serving? Why?
Sugar in one serving (g) = sugars per 100 ml × serving in ml ÷ 100. Write the full answer from your calculator.
Teaspoons = sugar in grams ÷ 4. Round to the nearest whole teaspoon.
Percentage of the 30 g daily limit = sugar in grams ÷ 30 × 100. Round to 1 decimal place.
| Drink | Working for sugar in one serving | Sugar (g) | Teaspoons | % of 30 g |
|---|---|---|---|---|
| F: Ras Sports, 500 ml | 4 × 500 ÷ 100 | 20 | 20 ÷ 4 = 5 | 20 ÷ 30 × 100 = 66.7% |
| A: Ffizz Cola, 330 ml | ||||
| B: Mellt Energy, 250 ml | ||||
| C: Haul Orange Juice, 150 ml | ||||
| D: Llaeth Mefus, 330 ml | ||||
| G: Sgwosh squash, 250 ml | ||||
| H: Ffynnon Water, 500 ml |
For now, count all the label sugar towards the 30 g. (Card D is a little different, because some of its sugar comes from the milk. There is a challenge about this at the end.)
(a) Look back at your Step 2 estimate for Ffizz Cola. Was it too big or too small? Why?
(b) Mellt Energy has more sugar per 100 ml than Ffizz Cola, but less sugar in one can. Explain how this can be true.
Cai is an invented Year 7 pupil from Aberystwyth. This is what he drinks on a school day. All the sugar in these drinks counts as free sugar. Use your answers from Step 3.
| When | Drink | Sugar (g) |
|---|---|---|
| Breakfast | 1 glass of Haul Orange Juice (150 ml) | |
| Break time | 1 bottle of Ras Sports Drink (500 ml). Cai is not doing any sport. | |
| Lunch | 1 can of Ffizz Cola (330 ml) | |
| After school | 2 glasses of Sgwosh squash (250 ml each) | |
| Evening | 1 bottle of Ffynnon Water (500 ml) | |
| Total sugar from drinks in one day | ||
(a) How many grams is Cai’s total over the 30 g daily limit? Show your working.
(b) What is his total as a percentage of 30 g? Round to 1 decimal place.
(c) About how many teaspoons of sugar is his total? Round to the nearest whole teaspoon.
(d) These totals are from Cai’s drinks only. Why does that make the answer to (a) more worrying?
Cai has the same drinks on every school day, 5 days a week. He is thinking about these swaps. Work out the free sugar after each swap. (Careful with swap C: the sugar in plain milk is natural milk sugar, which is not free sugar, so it counts as 0 g of free sugar.)
| Swap | Free sugar before (g) | Free sugar after (g) | Saved per day (g) | Saved per week (g) |
|---|---|---|---|---|
| A: Ffizz Cola can (330 ml) → Ffynnon Water (500 ml) | ||||
| B: Ras Sports Drink (500 ml) → Ffynnon Water (500 ml) | ||||
| C: Haul Orange Juice (150 ml) → Fferm Fach Milk (200 ml) | ||||
| D: Ffizz Cola can (330 ml) → Ffizz Cola mini can (150 ml) |
(a) Which swap saves the most sugar in a week? About how many teaspoons is that?
(b) Cai makes swaps A and B. Work out his new daily total from drinks. Is it now under 30 g? Show your working.
(c) Cai says: “Swapping to the mini can is pointless. It’s the same drink.” Use your numbers to reply.
Use the traffic light box on the stimulus. First colour each drink using the sugars per 100 ml. Then check the extra rule: if the serving is more than 150 ml and has more than 13.5 g of sugars, it is red.
| Drink | Colour from per 100 ml | Serving more than 150 ml? | Sugar in the serving (g) | Final colour |
|---|---|---|---|---|
| Ffizz Cola can (330 ml) | ||||
| Ffizz Cola mini can (150 ml) | ||||
| Haul Orange Juice (150 ml) | ||||
| Ras Sports Drink (500 ml) | ||||
| Sgwosh squash (250 ml) |
The 330 ml can of Ffizz Cola is red, but the 150 ml mini can is amber. It is exactly the same drink. Explain why the colours are different.
(a) Give 2 reasons why it is easy to have a lot of sugar from drinks without noticing.
(b) Write a short, friendly message to Cai (about 60 to 80 words). Suggest 2 swaps and use at least 3 numbers from your calculations to show why they help. Write about Cai only: do not write about what you eat or drink yourself.