New

Year 3

Add fractions with the same denominator

I can add fractions with the same denominator.

Download all resources

Share activities with pupils

New

Year 3

Add fractions with the same denominator

I can add fractions with the same denominator.

Download all resources

Share activities with pupils

These resources will be removed by end of Summer Term 2025.

Switch to our new teaching resources now - designed by teachers and leading subject experts, and tested in classrooms.

View new resources

Slide deck

Download slide deck

Skip slide deck

Lesson details

Key learning points

If fractions have the same denominator they can be added.
If 2 plus 3 is equal to 5 then 2 one sevenths plus 3 one sevenths is equal to 5 one sevenths.
To add fractions with the same denominator you use the language of unitising.

Keywords

Units - The unit is one of something that defines the ‘one’ you are counting in.
Denominator - A denominator is the bottom number in a fraction. It shows how many parts a whole has been divided into.
Numerator - A numerator is the top number in a fraction. It shows how many parts we have.

Common misconception

Typically, many children add both the numerators and denominators together to get the sum.

Pupils need to grasp units and unitising. Get them to move around the classroom/school performing simple additions with different sets of objects. Revisit fractions explaining that they're using unit fractions and this is shown by the denominator.

You may want to provide the children with the chance to create their own representation of the watermelon slice calculation in the first lesson cycle before discussing what the Oak characters come up with. This will give ownership to the class.

Teacher tip

Licence

This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).

Lesson video

Skip lesson video

Worksheet

Download worksheet

Skip worksheet

Starter quiz

Download starter quiz

6 Questions

Q1.

Which of these definitions describes an addend?

Correct answer: A number added to another number.

All of the parts added together.

Q2.

What is the missing number in this bar model?

Correct Answer: 3, three

Q3.

What addition is being shown by this number line?

2 + 3 = 5

Correct answer: 5 = 3 + 2

2 + 5 = 3

3 = 2 + 5

Q4.

A melon is cut into eight equal parts. What fraction is each part?

$$ \frac{2}{8} $$

Correct answer: $$ \frac{1}{8} $$

$$ \frac{1}{6} $$

$$ \frac{1}{7} $$

Q5.

How could we show the whole represented in this bar model using fraction notation?

Correct answer: $$ \frac{5}{5} $$

$$ \frac{4}{4} $$

$$ \frac{3}{3} $$

$$ \frac{2}{2} $$

Q6.

When the numerator and denominator are the same, what do we know about the value of the fraction?

Correct answer: It’s equivalent to one whole.

Correct answer: It’s equivalent to 1

It’s equivalent to 0

Exit quiz

Download exit quiz

6 Questions

Q1.

Look at the picture. What is the unit of this addition?

Ones

Correct answer: Bears

Numerals

Q2.

Look at the image. What is the missing label marked with a question mark?

addend

Correct answer: sum

part

Q3.

What addition is being represented on this number line?

$$ \frac{6}{8} $$ + $$ \frac{3}{8} $$ = $$ \frac{3}{8} $$

$$ \frac{1}{8} $$ + $$ \frac{5}{8} $$ = $$ \frac{6}{8} $$

$$ \frac{6}{8} $$ + $$ \frac{5}{8} $$ = $$ \frac{1}{8} $$

Correct answer: $$ \frac{3}{8} $$ + $$ \frac{3}{8} $$ = $$ \frac{6}{8} $$

Q4.

Which is the correct sum for this equation? $$ \frac{3}{9} $$ + $$ \frac{2}{9} $$ = ___

$$ \frac{5}{18} $$

Correct answer: $$ \frac{5}{9} $$

$$ \frac{1}{9} $$

Q5.

Which is the correct sum for this equation? ___ = $$ \frac{2}{12} $$ + $$ \frac{6}{12} $$

$$ \frac{12}{24} $$

$$ \frac{8}{24} $$

Correct answer: $$ \frac{8}{12} $$

Q6.

Which equation matches the problem? A pizza is cut into 6 slices. Sam eats three slices and Sofia eats one slice. What fraction of the pizza has been eaten?

Correct answer: $$ \frac{3}{6} $$ + $$ \frac{1}{6} $$ = $$ \frac{4}{6} $$

$$ \frac{3}{6} $$ + $$ \frac{1}{6} $$ = $$ \frac{6}{6} $$

$$ \frac{6}{6} $$ + $$ \frac{1}{6} $$ = $$ \frac{4}{6} $$