Adding and subtracting fractions with like denominators – Grade 4 math lesson
US version. US grades, US spelling and dollars ($). · UK Maths Department
A complete 45-minute lesson for grade 4 (ages 9–10) that runs on this page – at school or at home. Every answer is graded right away, with a worked explanation.
- Time
- 45 minutes + 20 min homework
- Grade
- Grade 4 (ages 9–10)
- You need
- Paper, a pencil and this page
- Graded
- Instantly, with explanations
For parents: how to use this lesson
You don't need to know this topic yourself. The lesson explains each step on screen, the way Mr Euclid, our Head of Math, likes it: one tidy step at a time. Every answer is graded straight away with a worked explanation, so you never have to grade anything.
- Read what your child will learn together.
- Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
- Let them do the practice on their own. They choose Getting started, On track or Challenge – start on On track and move up after a few right in a row.
- Finish with the exit ticket and the talk question: “Why do we not add the denominators?”
- Later that day or the next day: the homework (20 minutes), then a practice test.
Watch out for
- Adding the denominators too (2/7 + 3/7 = 5/14). Ask "sevenths plus sevenths make…?" Sevenths stay sevenths.
- Subtracting the denominators to get 0. Use a bar split into the same number of parts and cross some out.
Miss Hypatia's tip for home: Use a chocolate bar or pizza to show adding equal-sized pieces.
What your child will learn
Learning goal: add and subtract fractions with the same denominator.
Success looks like
- I can add numerators when the denominators match.
- I keep the denominator the same.
- I can write an answer over one whole as a mixed number.
Key words
- numerator
- how many parts
- denominator
- what size the parts are
- improper fraction
- a fraction bigger than one whole, e.g. 9/6
- mixed number
- a whole number and a fraction, e.g. 1 1/2
What to have ready
- Paper and a pencil
- This page on a computer, tablet or phone
- For the hands-on part: Use fraction strips: lay out 2 sevenths and 3 sevenths end to end and count the sevenths. No fraction strips? Draw a bar split into equal parts and shade it.
The lesson, step by step
| Part | Time | How it is checked |
|---|---|---|
| Starter: quick recall | 5 min | Graded by Classfern |
| Teaching input | 10 min | Not assessed, self-checked |
| Worked examples and guided practice | 9 min | Not assessed, graded by Classfern |
| Independent practice | 15 min | Graded by Classfern |
| Closure and exit ticket | 6 min | Graded by Classfern, self-checked |
Starter, "your turn", practice and exit ticket are graded by Classfern. Worked examples and teaching are not assessed. The hands-on task and the reflection are self-assessed. Explanations in talk are judged by the parent and not recorded.
The lesson
It runs here on the page. No sign-up and no names – progress is kept only in this browser.
Homework and practice at home
20 minutes: 10 practice questions, 3 multiple-choice questions and 2 to remember from earlier work, then a short reflection. New questions every time, all graded instantly.
More practice
More Grade 4 math lessons
- Place value: the value of each digit
- Rounding to the nearest 10, 100 or 1,000
- Equivalent fractions
- Fractions of a whole number
- Decimals: tenths, hundredths and thousandths
- Area of rectangles
- Perimeter
- Finding unknown angles
- Converting units of time
- Money: totals and change
- Factors and multiples
- Prime and composite numbers
Curriculum
Common Core State Standards: ccss-ma-4-nf-b-3-a
Our lessons and questions are our own. They are not written or endorsed by any government department, testing agency or exam board.