Starter quiz
- Sam uses these counters to find the sum in an equation. Which number will be the sum?
- 5
- 4
- 9 ✓
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- Which numeral represents the amount added in the picture?
- 6
- 8
- 2 ✓
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- Write an equation to represent the picture.
- '3+1=4' ✓
- Which picture could represent this equation? 6 = 2 + 4
- This missing number equation represents the picture shown. 3 + ___ = 5 Which number is the missing addend?
- 2 ✓
- 3
- 5
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- Sam has 3 pens and Jacob has 4 pencils. When they put them together, they have a whole group of 7 objects. Which expression could represent the addends?
- 7 - 4
- 3 + 4 ✓
- 4 + 3 ✓
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Exit quiz
- Jacob describes this picture as 2 apples and 5 oranges. 7 pieces of fruit altogether. He writes 2 + 5 = 7. What equation would represent the story if the parts had been added in a different order?
- 7 - 2 = 5
- 5 + 2 = 7 ✓
- 7 + 2 = 5
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- Which Hungarian tens frame shows 4 + 2 = 2 + 4?
- Match the equations that show that the addends order can be changed but the sum will remain the same.
- 8 + 1 = 9⇔1 + 8 = 9 ✓
- 4 + 0 = 4⇔0 + 4 = 4 ✓
- 7 + 2 = 9⇔2 + 7 = 9 ✓
- What is the missing number from this equation to make it correct?
- '7' ✓
- Which of these equations is correct?
- 6 + 2 = 2 + 6 ✓
- 4 + 3 = 4 + 4
- 2 + 2 = 3 + 2
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- Alex says that 5 can be used to fill all the gaps in the equations. Tick the ones where 5 is the missing number.
- 3 + 2 = ___ + 3
- 2 + ___ = 5 + 2 ✓
- ___ + 3 = 3 + 5 ✓
- 4 + 1 = ___ + 4
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Worksheet
Presentation
Lesson Details
Key learning points
- When the order of the addends is changed, the sum remains the same.
- Addition is commutative because the addends can be combined in any order.
- An equation can be written to show that when the order of the addends is changed, they remain equal.
Common misconception
Children may not recognise the same equation when the order of the addends is swapped. They may also think of the equal sign as meaning' the answer is' rather than showing equivalence.
Demonstrate writing equation in different order to that seen in picture or present as mistake to discuss. Refer to equals sign as ‘is equals to’ rather than ‘makes’ or ‘is’ and vary its position in equations to draw attention to its meaning.
Keywords
Addend - part - Any of the numbers that are added together. A part of the whole.
Sum - whole - The result of adding two or more numbers.
Commutative - Addition is commutative because if order of the addends are change, the sum remains the same.
Altogether - To bring two or more numbers together and find out how many. The amount in the whole set or group.