Math lesson plan · 4th grade (Year 5 in England) · 45 minutes
Multiply multiples of 10, 100 and 1000 mentally
Multiplication and division
CCSS 4.NBT.B.5England: Y5 Multiplication and division
Objective and success criteria
Students will: Multiply multiples of 10, 100 and 1000 mentally.
- 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 whole numbers by 10, 100 and 1000
Leads to: Multiply two-digit numbers with an area model; Estimate products by rounding; Mental multiplication tricks: ×5, ×25, ×9, ×99 and doubling and halving
Materials: Counters for arrays, Multiplication grid, Base-ten blocks, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Multiply whole numbers by 10, 100 and 1000). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 170 × 10 = ? → 1700Prompt: Each digit moves 1 place to the left.
- 6 × __ = 600 → 100Prompt: How many places have the digits of 6 moved?
- Kai says 22 × 1000 = 2200. Spot the mistake and give the right answer. → 22000Prompt: How many zeros does 1000 have?
Hook · 5 min
- Show an array of chairs, eggs or windows and ask how many there are without counting one by one.
- Share the objective: Multiply multiples of 10, 100 and 1000 mentally. 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: 90 × 600 = ?
- Step 1: 9 × 6 = 54
- Step 2: 90 × 600 = 54 000
- Answer: 54000
- 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.
- 200 × 800 = ? → 160000Prompt: Start with the basic fact 2 × 8.
- 40 × 50 = ? → 2000Prompt: 4 × 5 = 20. Careful: this fact already ends in a zero.
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.
- Zoe needs 3600 tiles. They come in boxes of 40. How many boxes does Zoe need? → 90Prompt: 40 × ? = 3600
- 50 × 50 = ? → 2500Prompt: Start with the basic fact 5 × 5.
Watch out for
- Thinking multiplying always makes a number bigger.
- Dropping a zero in long multiplication when moving to the tens row.
Support and stretch
Support
- Review first: Multiply whole numbers by 10, 100 and 1000.
- Use concrete materials: counters for arrays.
- 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: Multiply two-digit numbers with an area model; Estimate products by rounding; Mental multiplication tricks: ×5, ×25, ×9, ×99 and doubling and halving.
- 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