Percentages — for parents
Percentages are one of the most useful topics in primary maths. Your child meets them in shops, on screens, in school marks and on sports broadcasts. The Year-5 goal is not deep algebra — it's the fluency to read and use percentages confidently in everyday life.
What your child should master
- The big idea: percent = "out of 100". The symbol `%` is shorthand for `/100`.
- Reading a percent off a 10 × 10 hundred-grid.
- The friendly equivalences by heart: 1/2 = 50 %, 1/4 = 25 %, 3/4 = 75 %, 1/5 = 20 %, 1/10 = 10 %, 100 % = the whole.
- Converting between percent and decimal by shifting the decimal point two places.
- Finding 10 % of a number by dividing by 10.
- Finding 50 %, 25 %, 75 % of a number using halving and quartering.
- A first feel for "of a quantity" — e.g. 20 % of 30 children is 6 children.
Common confusions
"30 % of 80" mistaken for "80 − 30"
The child treats the percent as a number to subtract.
Help: drill the rule "of means multiply" — by either the decimal (× 0.30) or the fraction (× 3/10). Use the hundred-grid: 30 squares out of 100 = 30 in every 100 = 24 out of 80.Confusing 100 % with 1 %
Both look like a single digit with a `%` sign, but they're a hundred times apart.
Help: anchor them — 100 % is the whole thing. 1 % is one part out of 100, a sliver.Always thinking percentages are less than 100
A percent can be more than 100 ("125 % of last year's sales"). It just means more than the whole.
Help: show this on a number line or a sales chart. 125 % is 1.25 — a quarter more than the whole.Adding percents without thinking about the base
"A 20 % discount, then a 10 % discount" is not a 30 % discount. The second discount applies to the already-reduced price.
Help: at home, calculate a two-step discount on a real shop price. Children love finding that the answer is less than they expected.Activities at home
Shop receipts
When you buy something on sale, ask your child to work out the discount in pounds (or your currency).
"This bag was £40, it's 25 % off. How much do we save? How much do we pay now?"
Battery percent estimator
Ask your child to estimate the battery percent before showing them the actual number. After a week of practice they will be surprisingly accurate.
Score conversion
After any quiz or test that isn't out of 100 — say "17 out of 20" — ask your child to turn it into a percent.
Sales-rail percent game
In a clothes shop, point to a rail and ask: "What's 30 % off this £25 t-shirt?" Quick mental practice; the friendlier the price, the easier the maths.
"What's 1 % of …?"
A round-the-house game. "What's 1 % of 700?", "What's 1 % of 4500?". Knowing 1 % of any number is just dividing by 100 — a powerful starting point for any percent calculation.
Why this matters
Percentages are everywhere in adult life — VAT and tax rates, mortgage rates, election polls, sports stats, weather forecasts, interest on savings. The clean "out of 100" rule is the easiest kind of comparison to read, and that's exactly why it's used everywhere.
Get fluent at Year 5 and the rest is just bigger numbers — the idea never changes.