Decimals
This topic covers 5 learning steps, guiding your child from the basics through to confident problem-solving. Each step includes a worked example and adaptive practice questions.
What Your Child Will Learn
- Place Value with Decimals
Understand tenths and hundredths - Ordering Decimals
Compare and order decimal numbers - Add & Subtract Decimals
Calculate with decimal numbers - Multiply Decimals
Multiply decimals by whole numbers - Challenge — Decimal Word Problems
Multi-step problems with decimals
Before This Topic
Your child should be comfortable with:
Common Mistakes
- Thinking that a number with more decimal places is always bigger (e.g. thinking 0.15 > 0.3 because 15 > 3)
Compare decimals digit by digit from left to right: 0.3 = 0.30, which is bigger than 0.15. Use a number line or a place value chart to make this clear. Writing 0.3 as 0.30 helps children compare. - Reading 0.5 as "zero point five" but not understanding it means the same as 1/2 or 50%
Connect decimals to fractions: 0.5 = 5/10 = 1/2. Use money (£0.50 = 50p = half a pound) and measurement (0.5 m = 50 cm = half a metre) to make the link real.
Tips for Parents
- Use money to teach decimals naturally: £2.45 is "2 whole pounds and 45 hundredths of a pound." Children already use decimals when they use money.
- Measure things to the nearest tenth of a centimetre: "Your pencil is 15.3 cm long." This connects decimals to real measurement.
- Place decimals on a number line between whole numbers: "Where does 2.7 sit between 2 and 3?" This builds number sense.
- Convert between fractions and decimals using division: "1/4 means 1 ÷ 4 = 0.25." Practise with halves, quarters, fifths, and tenths.
Key Words
- Decimal — A number with a decimal point showing tenths, hundredths, etc. — like 3.75.
- Decimal point — The dot that separates the whole-number part from the fractional part — in 3.75, it sits between 3 and 75.
- Tenths — The first digit after the decimal point — in 3.7, the 7 means 7 tenths.
- Hundredths — The second digit after the decimal point — in 3.75, the 5 means 5 hundredths.
- Place value — The value of a digit based on its position — the 7 in 3.75 is worth 7/10, not 7.
Where This Fits
Before this topic: Children should understand fractions (including tenths and hundredths) and be familiar with place value in whole numbers.
After this topic: Decimal basics lead to ordering, rounding, and calculating with decimals, and to fluent conversion between fractions, decimals, and percentages in Year 6.
How MathCraft Teaches This
In MathCraft, Decimals is taught through the Money, Data & Measure adventure track. Your child follows guided lessons with friendly characters, works through examples step by step, then practises with questions that adapt to their level.
The adaptive engine tracks mastery across all 5 steps, revisiting concepts your child finds tricky and advancing when they're ready. Parents can see detailed progress in the Parent Dashboard.
Practise Decimals with MathCraft
Step-by-step lessons, worked examples, and adaptive practice — all wrapped in an adventure game your child will love.
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