Roman Numerals KS2
Facts, teaching ideas and a free ready-to-teach lesson
Teaching Roman numerals KS2 is an important part of the primary Maths curriculum, helping children understand number systems from the past while strengthening place value knowledge today.
From reading Roman numerals on clocks in Year 3 to recognising years written in Roman numerals in Year 5, pupils build their understanding gradually across Key Stage 2. Many children enjoy Roman numerals because they feel like solving a puzzle, making them a brilliant topic for engaging Maths lessons.
If you're teaching Roman numerals and want a ready-made lesson, you can download Lesson 5 from our Year 4 Place Value and Ordering scheme of work completely free. This lesson helps children read and write Roman numerals to 100 and includes everything you need to teach it confidently.
Free Roman Numerals KS2 Lesson Download
Grab your free Roman Numerals lesson
Our free Roman Numerals KS2 lesson is taken from Lesson 5 of our Year 4 Place Value and Ordering scheme of work.
In this lesson, children will:
- recap Roman numerals shown on analogue clocks
- read Roman numerals to 100 (I to C)
- write numbers using Roman numerals
- compare Roman numerals with our modern number system
- explore why the concept of zero changed Maths forever
The alternative activity challenges children to crack Roman numeral codes to help the Roman emperor uncover where rebels are hiding, making learning memorable and fun.
What’s included?
- detailed lesson plan
- teaching slides
- differentiated activities
- answer sheets
Roman Numerals Information for Children and Teachers
What are Roman numerals?
Roman numerals are a number system that was developed by the ancient Romans. It consists of a series of letters from the Latin alphabet that each have a fixed numerical value. By combining the letters together, any number can be made.
The letters used in the Roman numeral system are: I, V, X, L, C, D, M. These numbers represent, respectively: 1, 5, 10, 50, 100, 500 and 1000. By combining these letters in a particular way, any number can be represented.
How does the Roman numeral system work?
The Roman numeral system works by arranging the seven letters I, V, X, L, C, D and M in a particular way. Each value repeats its value the number of times it is written. For example:
XX is 10 + 10 = 20
CCC is 100 + 100 + 100 = 300
MM is 1000 + 1000 = 2000
If letters are placed after a letter of a greater value, you add the numbers together. For example:
VI is 5 + 1 = 6
LX is 50 + 10 = 60
XIII is 10 + 1 + 1 + 1 = 13
If letters are placed before a letter of a greater value, they are subtracted from the amount. For example:
IV is 5 - 1 = 4
IX is 10 - 1 = 9
XL is 50 - 10 = 40
You can only subtract powers of 10, so I, X and C (1, 10 and 100). This means you cannot subtract V or L (5 or 50). So 95, for example, is XCV (100 - 10 + 5) and not VC (100 - 5).
With Roman numerals, you never usually have more than three of the same letters consecutively. The exception to this is the number 4 on clocks with Roman numerals, which is often shown as IIII instead of IV. The number 4000 is also sometimes written as MMMM.
Did you know...?
Roman numerals can be written in upper or lower case letters. For example, 392 can be written as CCCXCII or cccxcii.
How to teach Roman numerals in KS2
Roman numerals can feel tricky at first, so practical examples help children understand the patterns.
Start with clocks
Most children first encounter Roman numerals on analogue clocks, making this the perfect starting point.
Focus first on:
- I to XII
- reading clock faces
- spotting patterns
- comparing Roman and modern numerals
This helps children make real-world connections before moving on to larger numbers.
Teach the rules clearly
Children need to understand that Roman numerals usually work by adding values together.
For example:
- VI = 6
- XII = 12
- LX = 60
They also need to learn subtraction rules:
- IV = 4
- IX = 9
- XL = 40
- XC = 90
Teaching these patterns explicitly helps avoid confusion.
Link Roman numerals to place value
Roman numerals are part of the Number and Place Value curriculum, so linking them to existing place value learning helps understanding.
Discuss:
- why Roman numerals have no zero
- why place value works differently
- how our number system improved over time
This helps deepen mathematical understanding rather than treating Roman numerals as a standalone topic.
Roman Numerals by year group
Roman Numerals Year 3
In Year 3, children are expected to:
tell and write the time from an analogue clock, including using Roman numerals from I to XII.
This is usually taught through time lessons using Roman numeral clock faces.
Children focus on:
- reading Roman numerals to 12
- telling the time
- comparing analogue and digital clocks
Roman Numerals Year 4
In Year 4, children must:
read Roman numerals to 100 (I to C) and know that over time, the numeral system changed to include the concept of zero and place value.
This is where Roman numerals become more challenging and children begin applying rules more independently.
Our free lesson download supports this objective directly.
Roman Numerals Year 5
In Year 5, children are expected to:
read Roman numerals to 1000 (M) and recognise years written in Roman numerals.
This often includes:
- reading dates on buildings
- recognising years in books and films
- converting between Roman and modern numerals
These lessons are often highly engaging because children can spot Roman numerals in everyday life.
Quick Roman Numerals Challenge
Can your class work these out?
- XVII
- XLII
- XCIX
- CXLV
- MCMXXXIX
These make excellent morning starters, plenaries or quick retrieval tasks.
You can also use our free Roman numerals lesson as a full classroom session with ready-made slides and differentiated activities.
Looking for more Roman Numerals KS2 resources?
If you’re teaching Roman numerals across KS2, these lesson packs provide full curriculum coverage:
Year 3 Time
Includes:
- units of time
- time duration
- telling the time on analogue clocks
- reading Roman numerals on analogue clocks
Year 4 Place Value and Ordering
Includes:
- four-digit numbers
- comparing and ordering
- counting in multiples
- Roman numerals to 100
Including the free Lesson 5 Roman Numerals lesson.
Year 5 A Million Numbers
Includes:
- reading Roman numerals
- Roman numeral years
- place value to 1,000,000
- comparing and rounding large numbers
Perfect for progression into Upper KS2.
Save time with ready-to-teach Roman Numerals lessons
Teaching Roman numerals doesn’t need to mean creating resources from scratch.
Our fully planned lessons include everything you need to teach confidently, save preparation time and ensure full National Curriculum coverage.
Start with your free Roman Numerals KS2 lesson download and help your class master Roman numerals with confidence.
