Fractions in Year 4 — for parents

Fractions in Year 4 are a big leap from Year 3. Before, fractions were just shaded pictures; now they behave like numbers — they have equivalents, they can be compared, added, subtracted and rewritten in two forms (mixed and improper). It's the year when fractions stop being decoration and start being arithmetic.

What your child should master

• Recognise and write equivalent fractions in both directions (find an equivalent / simplify to the simplest form).
• Compare two fractions with the same denominator, the same numerator, and (after rewriting) with any small denominators.
• Add and subtract fractions with the same denominator, including answers larger than 1.
• Convert between mixed numbers and improper fractions in both directions.
• Find a fraction of a set of objects (e.g. $\frac{3}{4}$ of 12 apples).
• Connect fractions to decimals for $\frac{1}{2}$, $\frac{1}{4}$, $\frac{3}{4}$ and $\frac{1}{10}$ (the start of the link with decimals).

Common mistakes

Adding the denominators

The classic. $\frac{1}{4}+\frac{2}{4}$ — child writes $\frac{3}{8}$.

Help: a quick picture — a pizza cut into 4 slices. Take 1 slice, then take 2 more. You have 3 slices out of 4, not 3 slices out of 8. The size of the slice doesn't change when you add.

Thinking a bigger denominator means a bigger fraction

"$\frac{3}{8}$ is bigger than $\frac{3}{4}$ because 8 is bigger than 4."

Help: a pizza picture again. Cutting a pizza into 8 slices makes each slice smaller, not bigger. Three small slices is less than three big slices.

Adding the same number to top and bottom for equivalents

Child writes $\frac{1}{2}=\frac{2}{3}$ (added 1 to top and 1 to bottom).

Help: the rule is multiply (or divide) by the same number, not add. Show that $\frac{2}{3}$ shaded is clearly more than $\frac{1}{2}$ shaded.

Forgetting to simplify

Child writes $\frac{5}{6}-\frac{2}{6}=\frac{3}{6}$ and stops. That's correct but not simplest — $\frac{3}{6}=\frac{1}{2}$.

Help: after every answer, ask "can the top and the bottom be divided by the same number?" If yes, simplify.

Confusing mixed and improper conversions

When converting $2\frac{3}{4}$ to improper, child writes $\frac{5}{4}$ (forgets to multiply 2 by 4 first).

Help: a clear two-step procedure — multiply, then add. $2\times 4=8$. $8+3=11$. Answer: $\frac{11}{4}$.

Using $\frac{1}{2}$ instead of computing fraction of a set

Child guesses "half" without doing the divide-by-bottom step.

Help: insist on writing the two steps: divide by the bottom, multiply by the top. Even for $\frac{1}{2}$ of 12, write 12 ÷ 2 × 1 = 6.

Activities at home

Pizza Friday

Cut a real pizza (or a paper one) into 8 slices. Talk about each slice as $\frac{1}{8}$. Take 3 slices — that's $\frac{3}{8}$. Eat 2 — what's left? Use the pizza for adding and subtracting. The picture sticks.

Equivalent-fraction bingo

You call out a fraction; your child writes three different equivalent fractions in 30 seconds. Score = number of correct equivalents.

Smaller or bigger?

You name two fractions; your child says which is bigger and why. Mix in pairs with the same denominator, same numerator, and different both.

Convert race

Write a list of mixed numbers on one side of paper and improper fractions on the other. Time your child as they convert each. Race their own previous time.

"How much of the cake is left?"

After dinner, when there's some cake or fruit left, ask "what fraction is left?". Encourage rough estimates first ("about a third"), then a more careful one if there are slices to count.

Why this matters

Fractions are the first stepping-stone to decimals, percentages, ratio, proportion, algebra — every later year leans on them. A child who finishes Year 4 with confident, automatic fraction arithmetic will have a smoother ride for the next five years. A child who clings to "pictures only" will hit a wall when fractions and decimals come together in Year 5.

What's next

• Back to the introduction
• Equivalent fractions
• Comparing fractions
• Worked examples