Math lesson plan · 5th grade (Year 6 in England) · 30 minutes
Common multiples and the lowest common multiple
Number sense
CCSS 6.NS.B.4England: Y6 Number – multiplication and division
Objective and success criteria
Students will: Common multiples and the lowest common multiple.
- 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: Recognise multiples of a number
Leads to: the next skill in this area.
Materials: Place value chart, Base-ten blocks or a number line, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Recognise multiples of a number). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- Which is a multiple of 10? (149 / 138 / 140 / 141) → 140Prompt: A multiple of 10 is in the 10 times table (or beyond it).
- How many multiples of 8 are there from 1 to 95? → 11Prompt: What is the biggest multiple of 8 that is not more than 95?
- Tariq says 73 is a multiple of 4. True or false? (true / false) → falsePrompt: Divide 73 by 4.
Hook · 3 min
- Show a number in the news or a price tag and ask what each digit is worth.
- Share the objective: Common multiples and the lowest common multiple. 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: What is the lowest common multiple of 3 and 4?
- Step 1: Multiples of 4: 4, 8, 12, 16, 20
- Step 2: 12
- Answer: 12
- 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.
- What is the lowest common multiple of 6 and 10? → 30Prompt: List multiples of 10: 10, 20, 30, …
- Two buses leave the station together at 8:00. One leaves every 15 minutes and the other every 20 minutes. After how many minutes do they next leave together? → 60Prompt: You need a time that is in both lists of departure times.
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.
- What is the lowest common multiple of 3 and 5? → 15Prompt: List multiples of 5: 5, 10, 15, …
- Two buses leave the station together at 9:00. One leaves every 10 minutes and the other every 15 minutes. After how many minutes do they next leave together? → 30Prompt: You need a time that is in both lists of departure times.
Watch out for
- Reading 1,045 as one thousand four hundred five: point to each place and say its value.
- Thinking a longer number is always bigger, even with decimals (0.45 vs 0.5).
Support and stretch
Support
- Review first: Recognise multiples of a number.
- Use concrete materials: place value chart.
- 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-5.
Free lesson plan from eurekami.com/lesson-plan-builder