New
New
Year 6
Solving calculations efficiently
I can explain how to solve calculations efficiently.
New
New
Year 6
Solving calculations efficiently
I can explain how to solve calculations efficiently.
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Lesson details
Key learning points
- Fluent calculation requires flexibility to move between mental and written methods and supports us to be efficient.
- Looking at the numbers within a calculation supports us to know whether to use a mental strategy or written method.
- Mental strategies work best when known facts are used.
- Written methods work best when the numbers given are precise or when exchanging is involved.
Keywords
Efficient - Being efficient means finding a way to solve a problem quickly whilst also maintaining accuracy.
Precise - Being precise is being exact. In this case, it is when numbers are given as exact values and are not rounded.
Common misconception
Children may automatically use a formal written algorithm. Children may not see the difference between, 'How much more?' and 'How many times more?'
What do you notice about the numbers? Is there a more efficient way? Can you represent this in a bar model or form an equation. What do you notice about the language?
This lesson needs children to really notice the numbers in a calculation. Use the question, 'What do you notice?' to get the children to think deeply and reason about the calculations.
Teacher tip
Licence
This content is © Oak National Academy Limited (2024), licensed on
Open Government Licence version 3.0
except where otherwise stated. See Oak's terms & conditions (Collection 2).Lesson video
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Starter quiz
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6 Questions
Q1.
Look at this table. What is the average mass of a blue whale?
1,400 kg
4,000 kg
30,000 kg
40,000 kg
Q2.
Using this equation, what else can you determine? 300 + 450 = 750
750 + 300
750 + 450
Q3.
Complete the missing value: 145,000 = 100,000 + + 5,000
Q4.
Match the factors to their product.
120
10,200
1,030
130
1,300
Q5.
Lucas wins 5,000 points in a game. Aisha wins 2,500 points in the same game. How many more points does Lucas win? points
Q6.
Aisha wins 24,506 points in a game and Lucas wins 913 points. How many points do they win in total? points
Exit quiz
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6 Questions
Q1.
Written methods are often most efficient to use to solve problems when the numbers __________.
are large
are small
are rounded
Q2.
Mental strategies methods are often most efficient to use to solve problems when the numbers __________.
are large
are small
are precise
need regrouping
Q3.
Look at the table. How much taller is Mount Everest than K2? m
Q4.
Look at the table. What is the combined height of Scafell Pike, Table and Ben Nevis? m
Q5.
Look at the table showing distances to some cities from London. How much further is it to New York than Paris? m
Q6.
Look at the table showing distances to some cities from London. Lucas’ dad flies to New Delhi and his mum flies to Oslo. What is the combined distance that they flew? m