Math lesson plan · 6th grade (Year 7 in England) · 30 minutes
Divide fractions by fractions
Fractions
CCSS 6.NS.A.1England: Y6 FractionsEngland: KS3 Number
Objective and success criteria
Students will: Divide fractions by fractions.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Divide unit fractions and whole numbers; Multiply fractions
Leads to: Divide mixed numbers; Reason about fraction division: method and size of the answer; Multiply and divide negative fractions and decimals
Materials: Fraction strips or a fraction wall, Paper strips to fold, Number lines, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Divide unit fractions and whole numbers; Multiply fractions). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 8 ÷ 1/5 = ? → 40Prompt: How many fifths are in one whole?
- 2 ÷ 1/3 = ? → 6Prompt: How many thirds are in one whole?
- 5 ÷ 1/7 = ? → 35Prompt: How many 1/7s are in one whole?
Hook · 3 min
- Cut a pizza or a strip of paper unevenly and ask whether the pieces are really halves or quarters.
- Share the objective: Divide fractions by fractions. Read the success criteria together.
I do: model it · 7 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: 2/3 ÷ 2/5 = ? Give your answer in simplest form.
- Step 1: 2/3 ÷ 2/5 = 2/3 × 5/2
- Step 2: = 10/6
- Step 3: = 5/3
- Answer: 5/3 (1 2/3)
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 6 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- 1/8 ÷ 1/4 = ? Give your answer in simplest form. → 1/2Prompt: Dividing by a fraction is the same as multiplying by its reciprocal.
- Chloe has 4 cups of flour. Each batch of pancakes needs 1/3 cup. How many batches can Chloe make? → 12Prompt: How many groups of the batch size fit into the total? That is division.
You do: independent practice · 7 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 6 questions are on the student sheet below, with answers in the key.
Exit ticket · 3 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- 2 1/4 ÷ 1/4 = ? (Simplest form; an improper fraction is fine.) → 9Prompt: Change the mixed number into an improper fraction first.
- 1/2 ÷ 1/3 = ? Give your answer in simplest form. → 3/2 (1 1/2)Prompt: Dividing by a fraction is the same as multiplying by its reciprocal.
Watch out for
- Thinking a bigger denominator means a bigger fraction (1/8 > 1/4).
- Adding the denominators when adding fractions (1/2 + 1/3 = 2/5).
Support and stretch
Support
- Review first: Divide unit fractions and whole numbers.
- Use concrete materials: fraction strips or a fraction wall.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: Divide mixed numbers; Reason about fraction division: method and size of the answer; Multiply and divide negative fractions and decimals.
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-6.
Free lesson plan from eurekami.com/lesson-plan-builder