Number - Fractions (including decimals and percentages)

KS2

MA-Y6-D003

Simplifying fractions using common factors; comparing and ordering fractions greater than one; adding and subtracting fractions with different denominators and mixed numbers; multiplying simple pairs of fractions; dividing fractions by whole numbers; computing decimal calculations to three decimal places; expressing fractions as decimals and percentages.

National Curriculum context

Year 6 fractions work represents the culmination of the primary fraction strand, which began with equal sharing in EYFS and progressed through unit fractions, equivalent fractions, and operations with like denominators across KS1 and lower KS2. Pupils now encounter the full range of fraction arithmetic — adding and subtracting fractions with different denominators, multiplying fractions together, and dividing fractions by whole numbers — equipping them with the conceptual and procedural tools needed for the rational number work of KS3. The explicit link between fractions, decimals and percentages, developed progressively since Year 4, is consolidated here so that pupils can fluently move between representations according to context, an essential skill for proportion reasoning and data interpretation. Simplification of fractions using highest common factors connects fraction work to pupils' developing understanding of multiplicative structure and factors. This domain also addresses the important concept of fractions as operators (a fraction of a quantity) and as measures, helping pupils develop flexible thinking about fractions beyond the part-whole model.

4

Concepts

2

Clusters

6

Prerequisites

4

With difficulty levels

AI Direct: 4

Lesson Clusters

1

Simplify, compare and add fractions with different denominators

introduction Curated

Simplifying/comparing fractions and adding/subtracting with different denominators are co-taught (C008 lists C009 in co_teach_hints). Together they consolidate fraction arithmetic.

2 concepts Scale, Proportion and Quantity
2

Multiply and divide fractions and convert fluently between fractions, decimals and percentages

practice Curated

Fraction multiplication/division and fraction-decimal-percentage equivalences are the upper primary fraction targets. C011 co-teaches with C008.

2 concepts Scale, Proportion and Quantity

Teaching Suggestions (1)

Study units and activities that deliver concepts in this domain.

Fractions, Decimals and Percentages

Mathematics Pattern Seeking
CPA Stage: pictorial → abstract NC Aim: reasoning
fraction wall hundred square
fraction wall bar model for fraction of amounts equivalence table (fractions/decimals/%) number line with mixed numbers area model for fraction multiplication
Fluency targets: Simplify fractions using common factors; Add and subtract fractions with unrelated denominators; Multiply pairs of proper fractions and simplify the result; Divide proper fractions by whole numbers; Fluently convert between fractions, decimals and percentages for common equivalences

Prerequisites

Concepts from other domains that pupils should know before this domain.

Concepts (4)

Simplifying and Comparing Fractions

skill AI Direct

MA-Y6-C008

Mastery of simplifying fractions means pupils can divide the numerator and denominator of any fraction by their highest common factor to express it in its simplest form, and can compare and order fractions — including improper fractions and mixed numbers — by converting to a common denominator. A fully secure pupil understands that simplification does not change the value of the fraction, only its representation, and chooses to simplify at appropriate points in calculations rather than only at the end.

Teaching guidance

Develop simplification as a natural extension of equivalent fraction knowledge from Year 5: rather than multiplying up to find equivalents, pupils now divide down to find simpler equivalents. Explicitly connect to the HCF work in the calculation domain. Use fraction walls and number lines to verify that simplified fractions are equivalent to the original. For comparing fractions, progress from using benchmark fractions (less than ½, equal to ½, greater than ½) to converting to a common denominator. Include improper fractions and mixed numbers in comparison activities.

Vocabulary: simplify, simplest form, lowest terms, common factor, equivalent fraction, common denominator, improper fraction, mixed number, compare, order
Common misconceptions

When simplifying, pupils often divide by 2 (or another common factor) rather than the highest common factor, leaving fractions in a partially simplified state (e.g., simplifying 12/18 to 6/9 rather than 2/3). Some pupils believe a fraction with a larger numerator and denominator is always greater than one with smaller numbers. When comparing fractions with different denominators, pupils sometimes compare numerators or denominators in isolation rather than converting to a common denominator.

Difficulty levels

Entry

Simplifying fractions by dividing numerator and denominator by a common factor.

Example task

Simplify 8/12.

Model response: 8/12 = 4/6 = 2/3 (dividing by 2 twice) or 8/12 = 2/3 (dividing by 4, the HCF).

Developing

Comparing fractions by converting to a common denominator, including mixed numbers and improper fractions.

Example task

Which is larger, 5/8 or 7/12?

Model response: LCM of 8 and 12 is 24. 5/8 = 15/24. 7/12 = 14/24. 15/24 > 14/24, so 5/8 is larger.

Expected

Ordering a set of fractions, decimals and mixed numbers by converting to a common form, and simplifying complex fractions.

Example task

Order from smallest to largest: 3/4, 0.7, 2/3, 0.72.

Model response: Convert all to decimals: 3/4 = 0.75, 0.7, 2/3 = 0.666..., 0.72. Order: 2/3, 0.7, 0.72, 3/4.

CPA Stages

concrete

Using fraction walls and fraction strips to simplify fractions by overlaying equivalent strips, and comparing fractions by finding common pieces

Transition: Child simplifies by dividing numerator and denominator by HCF and compares using common denominators without strips

pictorial

Recording simplification steps on paper (dividing by common factors), converting to common denominators to compare, and ordering fractions including mixed numbers on number lines

Transition: Child simplifies to lowest terms in one step (using HCF) and compares fractions efficiently using the LCM as common denominator

abstract

Simplifying and comparing fractions mentally, including mixed numbers and improper fractions, and selecting the most efficient common denominator

Transition: Child simplifies and compares any fractions mentally, sometimes using benchmark fractions (1/2, 1/4) for efficient comparison

Delivery rationale

Upper primary maths (Y6) — most pupils at pictorial/abstract stage. AI can deliver with virtual representations.

Addition and Subtraction of Fractions with Different Denominators

skill AI Direct

MA-Y6-C009

Mastery means pupils can add and subtract any pair of fractions — including those with different denominators and mixed numbers — by converting to equivalent fractions with a common denominator, and can simplify the result. A fully secure pupil applies this fluently in both calculation and problem-solving contexts, chooses the lowest common multiple of the denominators as the common denominator for efficiency, and manages the whole-number and fractional parts of mixed numbers correctly during subtraction.

Teaching guidance

Use fraction diagrams and number lines to demonstrate why fractions must have the same denominator before they can be added or subtracted. Progress carefully through three stages: same denominators (already secured), one denominator is a multiple of the other (simpler case), and denominators that share only the factor 1 (requiring multiplication of both). For mixed numbers, teach both the 'convert to improper fraction' method and the 'deal with whole and fractional parts separately' method, allowing pupils to choose. Subtraction of mixed numbers where regrouping is required (e.g., 3 1/4 - 1 3/4) needs careful attention.

Vocabulary: common denominator, equivalent fraction, lowest common multiple, mixed number, improper fraction, simplify, denominator, numerator
Common misconceptions

The classic and persistent misconception is adding numerators and denominators separately (e.g., 1/3 + 1/4 = 2/7). Use diagrams extensively to show why this is incorrect. When subtracting mixed numbers, pupils often subtract the smaller fraction from the larger regardless of which is the subtrahend (e.g., computing 3 1/4 - 1 3/4 as 3 + (3/4 - 1/4) = 3 2/4). Failing to simplify the final answer is also common; build simplification into the routine.

Difficulty levels

Entry

Adding and subtracting fractions with the same denominator, including mixed numbers.

Example task

Work out 2 3/7 + 1 5/7.

Model response: 2 + 1 = 3. 3/7 + 5/7 = 8/7 = 1 1/7. Total: 3 + 1 1/7 = 4 1/7.

Developing

Adding and subtracting fractions with different denominators by finding a common denominator.

Example task

Work out 5/6 – 2/9.

Model response: LCM of 6 and 9 is 18. 5/6 = 15/18. 2/9 = 4/18. 15/18 – 4/18 = 11/18.

Expected

Adding and subtracting mixed numbers with different denominators, simplifying results, in problem contexts.

Example task

A recipe uses 2 1/3 cups of flour and 1 3/4 cups of sugar. How much more flour than sugar? Simplify.

Model response: 2 1/3 – 1 3/4. Convert: 2 4/12 – 1 9/12. Borrow 1 from 2: 1 16/12 – 1 9/12 = 7/12 cup more flour.

CPA Stages

concrete

Using fraction strips to demonstrate adding and subtracting fractions with different denominators by converting to common-sized pieces first

Transition: Child finds common denominators and adds/subtracts without strips, converting to mixed numbers when results exceed 1

pictorial

Recording equivalent fraction conversions on paper, adding and subtracting mixed numbers using both the 'improper fraction' and 'separate whole/fraction' methods

Transition: Child adds and subtracts mixed number fractions on paper using either method, handling regrouping in subtraction

abstract

Adding and subtracting fractions and mixed numbers with different denominators fluently, simplifying results

Transition: Child performs any fraction addition or subtraction fluently, selecting the LCM and simplifying the result

Delivery rationale

Upper primary maths (Y6) — most pupils at pictorial/abstract stage. AI can deliver with virtual representations.

Multiplication and Division of Fractions

skill AI Direct

MA-Y6-C010

Mastery of fraction multiplication means pupils can multiply a pair of proper fractions by multiplying the numerators and the denominators, simplify the result, and understand the result is smaller than either factor (when both are proper fractions). For division of a fraction by a whole number, mastery means pupils understand that dividing a fraction by n is the same as multiplying by 1/n (or equivalently, multiplying the denominator by n) and can apply this in context.

Teaching guidance

For multiplication, begin with the concrete context of 'a fraction of a fraction' (e.g., ½ of ¾ of a pizza). Diagrams showing a rectangle divided first into quarters horizontally and then into halves vertically make the multiplication of fractions visually clear. Establish the rule (multiply numerators, multiply denominators) and connect it to the diagram. Cross-cancellation (simplifying diagonally before multiplying) can be introduced to keep numbers manageable. For division by a whole number, use sharing contexts: if ¾ of a bar of chocolate is shared equally between 3 people, each person gets ¼. Generalise to the rule of multiplying the denominator.

Vocabulary: multiply fractions, divide fractions, product, proper fraction, simplify, cross-cancel, reciprocal
Common misconceptions

Pupils apply addition/subtraction strategies to multiplication (finding a common denominator before multiplying), which is unnecessary and leads to errors. When dividing a fraction by a whole number, pupils sometimes divide the numerator rather than multiply the denominator (e.g., computing 3/4 ÷ 3 as 1/4, which coincidentally gives the right answer, but using incorrect reasoning that fails for other examples like 3/4 ÷ 2). Build conceptual understanding alongside procedural competence.

Difficulty levels

Entry

Multiplying two proper fractions using the rule: multiply numerators, multiply denominators.

Example task

Work out 2/3 × 4/5.

Model response: 2 × 4 = 8. 3 × 5 = 15. Answer: 8/15.

Developing

Dividing a fraction by a whole number by multiplying the denominator.

Example task

Work out 3/4 ÷ 2.

Model response: 3/4 ÷ 2 = 3/(4×2) = 3/8.

Expected

Multiplying proper fractions with simplification (cross-cancellation), dividing fractions by whole numbers, and understanding that multiplying proper fractions gives a smaller result.

Example task

Work out 3/8 × 4/9 using cross-cancellation. Explain why the answer is smaller than both fractions.

Model response: Cross-cancel: 3 and 9 share factor 3 (3→1, 9→3). 4 and 8 share factor 4 (4→1, 8→2). So 1/2 × 1/3 = 1/6. The answer is smaller because you are taking a fraction of a fraction — a part of a part is smaller than either part.

CPA Stages

concrete

Using fraction circles and paper folding to show 'a fraction of a fraction' (multiplication) and sharing fraction pieces equally (division by a whole number)

Transition: Child explains why multiplying fractions gives a smaller result and why dividing a fraction by n multiplies the denominator by n

pictorial

Drawing area models (rectangles divided horizontally and vertically) to show fraction multiplication, and bar models for fraction division, recording the calculation alongside

Transition: Child multiplies fractions by multiplying numerators and denominators, cross-cancelling first, and divides by multiplying the denominator

abstract

Multiplying and dividing fractions fluently, simplifying before multiplying when possible, and solving word problems involving fraction operations

Transition: Child multiplies and divides fractions fluently, using cross-cancellation for efficiency, and applies in context

Delivery rationale

Upper primary maths (Y6) — most pupils at pictorial/abstract stage. AI can deliver with virtual representations.

Fraction-Decimal-Percentage Equivalences

knowledge AI Direct

MA-Y6-C011

Mastery means pupils can fluently convert between fractions, decimals and percentages for a wide range of values, including less common equivalences such as 1/8 = 0.125 = 12.5%, and can select the most appropriate representation for a given context without prompting. A fully secure pupil understands that the three representations are different ways of expressing the same proportion and can use this understanding to compare quantities expressed in different forms and to solve proportion problems.

Teaching guidance

Build on the fraction-decimal-percentage equivalences established in Years 4 and 5 by extending to eighths, thirds and other fractions that produce recurring or multi-place decimals. Organised practice — completing equivalence tables, using sorting activities, and playing matching games — builds fluency. Percentage bar models support problem-solving: drawing a bar divided into 100 equal parts and shading the relevant percentage helps pupils visualise the relationship. Connect explicitly to the ratio domain by using percentages as a common scale for comparison.

Vocabulary: fraction, decimal, percentage, equivalent, convert, proportion, per cent, decimal point, recurring decimal
Common misconceptions

Pupils sometimes treat fractions, decimals and percentages as unrelated rather than as equivalent representations, failing to convert between them when it would be helpful. Common specific errors: believing 25% = ¼ but not knowing that 75% = ¾; confusing 0.5% with 50%; writing 0.8 as 0.8% rather than 80%. Regular work with real-world contexts (sale discounts, test scores, nutritional information) builds meaningful understanding alongside the procedural fluency.

Difficulty levels

Entry

Knowing the key fraction-decimal-percentage equivalences: 1/2 = 0.5 = 50%, 1/4 = 0.25 = 25%, 1/10 = 0.1 = 10%.

Example task

Write 3/4 as a decimal and a percentage.

Model response: 3/4 = 0.75 = 75%.

Developing

Converting between fractions, decimals and percentages including eighths, fifths and thirds.

Example task

Write 3/8 as a decimal. Write 0.2 as a fraction in simplest form. What percentage is 2/5?

Model response: 3/8 = 0.375. 0.2 = 1/5. 2/5 = 40%.

Expected

Converting any fraction, decimal or percentage and selecting the most useful form for a given context.

Example task

A shop reduces prices by 1/3. Is this more or less than a 30% discount? Show your working.

Model response: 1/3 = 33.3...% ≈ 33.3%. This is more than 30%. So a 1/3 discount is better for the customer.

Greater Depth

Ordering and comparing a mixture of fractions, decimals and percentages by converting to a common form, and justifying which form is most efficient for a given comparison.

Example task

Put these in order from smallest to largest: 0.375, 2/5, 37%, 3/8. Explain which form you used and why.

Model response: Convert to decimals: 0.375, 2/5 = 0.4, 37% = 0.37, 3/8 = 0.375. Order: 37% (0.37), then 0.375 and 3/8 (equal, both 0.375), then 2/5 (0.4). I used decimals because they are easiest to compare digit by digit. Fractions would need a common denominator of 200, which is harder.

CPA Stages

concrete

Using hundredths grids, money and fraction-decimal-percentage matching cards to explore equivalences including eighths (0.125) and thirds (0.333...)

Transition: Child converts between fractions, decimals and percentages for all common values including eighths and recognises recurring decimals for thirds

pictorial

Completing FDP conversion tables, drawing percentage bar models, and placing fractions, decimals and percentages on a single number line

Transition: Child converts between all three forms on paper and compares values expressed in different forms using a common representation

abstract

Converting between fractions, decimals and percentages mentally, selecting the most useful form for any given problem

Transition: Child selects the most efficient form for any calculation and converts fluently between all three representations

Delivery rationale

Upper primary maths (Y6) — most pupils at pictorial/abstract stage. AI can deliver with virtual representations.