Parents Numeracy Workshop

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Parents Numeracy Workshop

• Strategies for
• Addition Subtraction

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Maths is like Train-spotting you jot down a
whole load of numbers for no
apparent reason Cabbageyou either love it or
hate it depending on how it was
served up to you as a child
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Aims of session

• To discuss our response to your feedback at the
  last workshop.
• To consider briefly how maths is taught today.
• To consider the progression of addition and
  subtraction methods during primary school.

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Your feedback
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Key differences today

• Interactive teaching
• Emphasis on mental calculation
• Different approach to written calculation
• Maths through problem solving
• Maths is fun!

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The aim
The aim is for children to do mathematics in
their heads, and if the numbers are too large, to
use pencil and paper to avoid losing track. To
do this children need to learn quick and
efficient methods, including appropriate written
and mental methods.
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Mistakes children make
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16 - 9
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We want children to ask themselves
Can I do this in my head? Can I do this in my
head using drawings or jottings? Do I need to use
an expanded/compact written method? Do I need a
calculator? Finally is my answer sensible?
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Addition
How many altogether?
and
more
total
add
increase
sum
plus
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2 3 At a party, I eat 2 cakes and my friend
eats 3. How many cakes did we eat altogether?
Children could draw a picture to help them work
out the answer.
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8 4 8 people are on the bus. 4 more get on.
How many people are on the bus now?
Children could draw dots or lines, which is
quicker than drawing a picture.
???????????? or I I I I I I I I I I I I
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• 5 2
• 2 5
• 7 2
• 7 5
• Instead 5, 2, 7
• What sums can you make with these
  numbers?

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• Investigations
• Which two numbers could have a total of 15?
• Link to money, measure, etc.
• Choose 3 different coins that make 20p or less.
  What different amounts can you make?

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45 36 There are 45 boys in a school and 36
girls. How many altogether?
Children should partition (split) each number
into tens and units.
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Number line

• 76 47

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Expanded column addition
358 473
358 473
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120
700
831
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Column addition

• 2 3 4
• 3 5 7
• 1

5
1
9
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Column addition with numbers with up to two
decimal places

• 8 3 4
• 4 6 7 4
• 
  

0
4
1 3
1
0

1
1
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Subtraction
decrease
subtract
difference
less
fewer
minus
take away
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• Children are taught to understand subtraction as
  taking away (counting back) and finding the
  difference (counting up).

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5 - 2 I had five balloons. Two burst. How many
did I have left?
Children could draw a picture to help them work
out the answer.
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5 - 2 A teddy bear costs 5 and a doll costs
2. How much more does the bear cost?
Children could draw a picture to help them find
the difference.
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8 - 3 Mum baked 8 biscuits. I ate 3. How many
were left?
Children could draw dots or lines, which is
quicker than drawing a picture.
??????????? (find the difference) or I I
I I I I I I (take away)
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Number line count back
Imran has 13 conkers he gives 4 away to his
friends. How many does he have left? 13 4

- 1
- 1
- 1
- 1
13
12
11
9
10
9 conkers
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Number line count on
Imran has 43 conkers he gives 24 away to his
friends. How many does he have left? 43 - 24

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3
40
43
19p more
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54 - 38 There are 54 children in a school and
38 are poorly. How many are left at school?
Children should partition (split) each number
into tens and units.
54 - 38 30 8 54 - 30 24
24 - 8 16
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A sports stadium holds 9010 spectators. 5643
people attend a football match. How many empty
seats are there?
57
300
3010
5643
5700
9010
6000
3367 empty seats
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8.23 4.55 3.68
0.23
3
0.45
8.23
8.00
4.55
5.00
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Expanded Column Subtraction
663 378 ? 600 60 3 - 300 70 8

74 23 ? 70 4 - 20 3 50 1
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150
13
50
500
5
80
200
285
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Column subtraction
7
4
1

• 5 8 4
• - 3 9 7
• 7

1
1
8
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Column subtraction with decimals
1
3
7
4
1
0

• 5 8 4
• - 3 9 7 5

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If a number has less decimal places than another,
a zero may be used to help with the calculation.
Remember to place a decimal point in the answer.
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6
8
1
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• What happens next?
• There will be a multiplication and division
  workshop later this year.
• The PowerPoint will be uploaded onto the school
  website for you to use.

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• Any questions?