Adding and subtracting fractions with unlike denominators – Grade 5 math lesson

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.

1. Read what your child will learn together.
2. Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
3. 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.
4. Finish with the exit ticket and the talk question: “Why must the denominators be the same before you add?”
5. Later that day or the next day: the homework (20 minutes), then a practice test.

Watch out for

• Adding tops and bottoms (1/3 + 1/6 = 2/9). Check with a fraction wall: 2/9 is smaller than 1/3 on its own, so it cannot be right.
• Changing the denominator but not the numerator. Write the multiplier on both top and bottom with an arrow.

Miss Hypatia's tip for home: Use a measuring jug or recipe: 1/2 a cup plus 1/4 of a cup – how much altogether?