National curriculum content
- Add and subtract numbers with up to 4 digits using the formal written methods of columnar addition and subtraction where appropriate
- Estimate and use inverse operations to check answers to a calculation
- Solve addition and subtraction two-step problems in context, deciding which operations and methods to use and why
Lesson objectives
- Add and subtract 1s, 10s, 100s and 1,000s
- Add up to two 4-digit numbers - no exchange
- Add two 4-digit numbers - one exchange
- Add two 4-digit numbers - more than one exchange
- Subtract two 4-digit numbers - no exchange
- Subtract two 4-digit numbers - one exchange
- Subtract two 4-digit numbers - more than one exchange
- Efficient subtraction
- Estimate answers
- Checking strategies
What we want children to know
- Recognise patterns when we add and subtract 1, 10, 100s and 1,000s
- How to use their place value knowledge to confidently exchange in addition and subtraction calculations
- Confidently understand that we can only hold single digits in each column, anything over must be exchanged
- Learn to write formal written methods of column addition
- Be able to partition two-digit numbers in order to add and subtract from them
- Be able to confidently estimate an answer by using inverse methods to check answers
- How to independently select which operation methods to use when answering two-step problems
What skills we want children to develop
Use knowledge to solve Reasoning and Problem Solving questions such as:
Prove it
Rosie adds 2 numbers together that total 4,444. What could the numbers be? How many ways can you find?
Explain your reasoning
Jack says: “When I add two numbers together I will only ever make up to one exchange in each column.” Do you agree?
Mathematical Talk
- If we are adding tens, are the digits in the tens column the only ones that change?
- Can you represent ___ using the equipment?
- How many ones are there altogether? Can we make an exchange? Why?
- Why is it important to show the exchanged digit in the column method?
- Why is it important to line up the digits in the correct column when adding?
- How could you check your answer is correct?