Math lesson plan Β· 3rd grade (Year 4 in England) Β· 45 minutes
Subtract four-digit numbers in columns
Addition and subtraction
CCSS 4.NBT.B.4England: Y4 Addition and subtraction
Objective and success criteria
Students will: Subtract four-digit numbers in columns.
- 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: Subtract three-digit numbers with exchanging; Value of a digit in four-digit numbers
Leads to: Subtract numbers with more than four digits
Materials: Base-ten blocks, Number lines, Hundred square, Mini whiteboards and pens, Printed student sheet (below).
Warm-up Β· 5 min
- Quick retrieval from earlier learning (Subtract three-digit numbers with exchanging; Value of a digit in four-digit numbers). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 952 β 704 = ? β 248Prompt: Start with the ones.
- In 3619, which place is the digit 6 in? (ones / tens / hundreds / thousands) β hundredsPrompt: Name the places from the right: ones, tens, hundreds, thousands.
- 902 β 547 = ? β 355Prompt: There is a 0 in the tens. Exchange from the hundreds first.
Hook Β· 5 min
- Give a real shopping total or a score difference and ask for a quick estimate first.
- Share the objective: Subtract four-digit numbers in columns. Read the success criteria together.
I do: model it Β· 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: 9991 β 3388 = ?
- Step 1: ones: exchange, 11 β 8 = 3
- Step 2: tens: 8 β 8 = 0
- Step 3: hundreds: 9 β 3 = 6
- Step 4: thousands: 9 β 3 = 6
- Step 5: 9991 β 3388 = 6603
- Answer: 6603
- Pause after each step and ask a student to say what comes next.
We do: guided practice Β· 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.
- 7808 β 1290 = ? β 6518Prompt: Work from the ones to the thousands.
- 7000 β 5662 = ? β 1338Prompt: The zeros mean you exchange across several columns.
You do: independent practice Β· 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 Β· 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- 7000 β 2093 = ? β 4907Prompt: The zeros mean you exchange across several columns.
- 9394 β 7458 = ? β 1936Prompt: Work from the ones to the thousands.
Watch out for
- Subtracting the smaller digit from the bigger one in every column (52 β 17 = 45).
- Forgetting to add the regrouped (carried) ten.
Support and stretch
Support
- Review first: Subtract three-digit numbers with exchanging.
- Use concrete materials: base-ten blocks.
- 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: Subtract numbers with more than four digits.
- 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-3.
Free lesson plan from eurekami.com/lesson-plan-builder