Math lesson plan · 5th grade (Year 6 in England) · 45 minutes
Divide a decimal by a whole number
Decimals and percentages
CCSS 5.NBT.B.7England: Y6 Multiplication and division
Objective and success criteria
Students will: Divide a decimal by 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 decimal by a whole number; Divide a three-digit number by a one-digit number
Leads to: Decimal multiplication and division problems; Compare prices to find the better buy
Materials: Place value chart with tenths and hundredths, Hundred squares, Number lines, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Multiply a decimal by a whole number; Divide a three-digit number by a one-digit number). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 9.1 × 8 = ? → 72.8Prompt: Work out 91 × 8 first.
- 322 ÷ 2 = ? → 161Prompt: Divide the hundreds first, then the tens, then the ones.
- A bus ticket costs $6.41. Diego buys 4 tickets. What is the total cost? → 25.64Prompt: Multiply 6.41 by 4.
Hook · 5 min
- Show two prices or race times with decimals and ask which is bigger, then why.
- Share the objective: Divide a decimal by 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: 12.8 ÷ 4 = ?
- Step 1: 128 ÷ 4 = 32
- Step 2: 12.8 ÷ 4 = 3.2
- Answer: 3.2
- 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.
- 55.8 ÷ 6 = ? → 9.3Prompt: Divide as if it were a whole number.
- 4 friends share a bill of $24.44 equally. How much does each pay? → 6.11Prompt: Work out 24.44 ÷ 4.
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.
- 2 friends share a bill of $18.58 equally. How much does each pay? → 9.29Prompt: Work out 18.58 ÷ 2.
- 48.8 ÷ 8 = ? → 6.1Prompt: Divide as if it were a whole number.
Watch out for
- Thinking 0.45 is bigger than 0.5 because 45 is bigger than 5.
- Moving the digits the wrong way when multiplying or dividing by 10.
Support and stretch
Support
- Review first: Multiply a decimal by a whole number.
- Use concrete materials: place value chart with tenths and hundredths.
- 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: Decimal multiplication and division problems; Compare prices to find the better buy.
- 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