Math lesson plan · 4th grade (Year 5 in England) · 45 minutes
Word problems: a fraction times a whole number
Fractions
CCSS 4.NF.B.4.CEngland: Y5 Fractions
Objective and success criteria
Students will: Word problems: a fraction times a whole number.
- 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: Multiply a fraction by a whole number
Leads to: the next skill in this area.
Materials: Fraction strips or a fraction wall, Paper strips to fold, Number lines, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Multiply a fraction by a whole number). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 6 × 1/8 = ? (Give a fraction; it may be improper.) → 6/8Prompt: 6 lots of 1/8 is the same as adding it 6 times.
- Each smoothie uses 1/4 cup of yogurt. Maya makes 6 smoothies. How many cups of yogurt is that? (Simplest form; a whole or mixed number is fine as a fraction.) → 3/2 (1 1/2)Prompt: Multiply the amount for one smoothie by the number of smoothies.
- 5 × 2/6 = ? (Give a fraction; it may be improper.) → 10/6 (1 4/6)Prompt: 5 lots of 2/6 is the same as adding it 5 times.
Hook · 5 min
- Cut a pizza or a strip of paper unevenly and ask whether the pieces are really halves or quarters.
- Share the objective: Word problems: a fraction times a whole number. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Amara drinks 1/2 of a litre of milk every day. How much milk is that in 3 days? (Write a mixed number or whole number.)
- Step 1: 3 × 1/2 = 3/2
- Step 2: 1 1/2
- Answer: 3/2 (1 1/2)
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Zoe drinks 1/2 of a litre of milk every day. How much milk is that in 6 days? (Write a mixed number or whole number.) → 3Prompt: Work out 6 × 1/2.
- Which calculation finds 2 groups of 1/3? (2 + 1/3 / 2/3 × 1/3 / 1/6 / 2 × 1/3) → 2 × 1/3Prompt: 'Groups of' means multiply.
You do: independent practice · 10 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 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- Felix drinks 1/4 of a litre of milk every day. How much milk is that in 9 days? (Write a mixed number or whole number.) → 9/4 (2 1/4)Prompt: Work out 9 × 1/4.
- Which calculation finds 5 groups of 1/5? (5/5 × 1/5 / 5 + 1/5 / 5 × 1/5 / 1/25) → 5 × 1/5Prompt: 'Groups of' means multiply.
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: Multiply a fraction by a whole number.
- 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
- 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-4.
Free lesson plan from eurekami.com/lesson-plan-builder