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Westfield Middle School Visual Calculation Policy

Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

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Page 1: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Westfield Middle School

Visual Calculation Policy

Page 2: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Choosing a method

Addition methods

Subtraction methods

Multiplication methods

Division methods

About this policy

Page 3: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Can I use a mental strategy?

Should I use a written method?

Can drawings or objects help me?

Choosing a method

Page 4: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Use this technique when answering word

problems

Page 5: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Addition

Sum Total

Add

Plus

Count on Altogether

More

Increase

Page 6: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Addition – Counting

Divisor

4 + 3 = 7

Page 7: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

1. Addition – Counting on

0 1 2 3 4 5 6 7 8 9 10

6 + 3 = 9

Use numbered number lines to add, by counting on in ones.

Start with the larger number and count on.

+ 1 + 1 + 1

Page 8: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

2. Addition – Leaping Further

63 73 79

63 + 16 = 79

+ 10 + 6 Use empty number lines and hundred squares to build confidence when

adding 2 digit numbers.

Page 9: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

3 . Addition – Partitioning

27 + 12 = 39

20 7+ 10 2 30 + 9 = 39

Page 10: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

T U

+ 2 3 1 7 1 0 3 0 4 0

H T U

+ 2 3 6 7 3 9 1 0 0 2 0 0 3 0 9

4. Addition – Expanded Column

Add the units first in preparation

for the compact method

Page 11: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

5 . Addition – Compact Column Move from

expanded addition to the

compact column method,

adding units first, and ‘carrying’ numbers

underneath the

calculation.

Th H T U

+ 3 5 1 7 3 9 6 3 9 1 3

1 1

Remember this number is 500 not

5.

Start with the units

Carry any numbers underneath.

Page 12: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

The decimal point should be aligned in

the same way as the other place

value columns, and must be in the same

column in the answer

6. Addition – Compact ColumnIncluding decimals

+ 2 3 . 5 9 7 . 5 5 3 1 . 1 4

1 1 1

Page 13: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Subtraction

Take away

Minus

Count back

Fewer

Subtract

Less

Difference

between

Page 14: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Subtraction – Take away

Divisor

9 - 3 = 6

=

Page 15: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

1. Subtraction – Finding the difference

7 is 3 more than 4

.

Page 16: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

2. Subtraction – Counting back

0 1 2 3 4 5 6 7 8 9 10

7 – 3 = 4

Model subtraction using hundred squares,

numbered number lines and practically.

Page 17: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

3. Subtraction – Leaping Back

24 25 26 27 37 47

47 – 23 = 24

Partition the second number and subtract

the tens first

-10-1-1-1

Page 18: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

3. Subtraction – Counting On

89 99 102

102 – 89 = 13

+3

Continue to reinforce counting on as a strategy for close

together numbers and also for numbers that are nearly multiples of

10, 100, 1000 or £s

Start at the smaller number and count on in tens first, then

count on in units to find the rest of

the difference

+10

Page 19: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

2 0 0 + 3 0 + 8 1 0 0 + 4 0 + 6

0 + 9 0 + 2 =

4. Subtraction – Expanded column

100 Once pupils are secure with the understanding

of‘ ‘exchanging’, they can

use the partitioned column method to

subtract any 2 and 3-digit numbers.

1

238 – 146 = 92

Use vocabulary ‘steal’ or ‘take’ not ‘borrow’.

Page 20: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

5. Subtraction – Compact Column Th H T U

2 7 5 4 - 1 5 6 2 1 1 9 2

6 1

Children who are still not secure with number

facts and place value will need

to remain on the partitioned

column method until ready for the compact

method.

Page 21: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

6 . Subtraction – Compact Column with decimals

1 0 5 . 4 0 9 - 3 9 . 0 8 0 6 6 . 3 2 9

Empty decimal places can be

filled with zero to show the

place value in each column.

130 19 1

Page 22: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Multiplic

ation

Multiple

Groups of

Repeated

addition

Multiply

Lots of

Product

Times

Page 23: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Multiplication - Repeated Addition

8 + 8 + 8 = 24

Spiders have 8 legs. How many legs do 3 spiders have

altogether?

Page 24: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

1. Multiplication - Repeated Addition

There are 3 sweets in a bag and 3 bags of sweets. How many sweets

altogether?

Page 25: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

2. Multiplication - Arrays

3 X 7 = 21 or 7 X 3 = 21

Page 26: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

3 .Multiplication – The Grid Method

300

20

7

4

1200

80

28 1308

Make sure you do not add the 4

in the total

Partition the number into the

grid

Page 27: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

4. Multiplication – Expanded Column Method

Short

Multiplication

3 2 7 X 4 2 8 8 01 2 0 0

1 3 0 8

Page 28: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

5. Multiplication – The Grid Method

Long Multiplicatio

n 10

10

8

3

100 80

30 24

1 8 0

+ 5 4

2 3 4

18 X 13 = 234

Page 29: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

5. Multiplication – Expanded Column Method

Long

Multiplication

2 6X 1 4 2 4 8 0 6 02 0 0 3 6 4

1

Page 30: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

6. Multiplication – Decimals

Include

multiplying more complex

numbers and decimals.

3 . 1 9.

2 5 . 5 2

Remember place value, make sure numbers are in

the correct column.

8x

71

Page 31: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Division

Share

Divide

Quotient

Remainder

Halve

Equal groups of

Factor

Divisor

Page 32: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

1 . Division –Sharing

15 ÷ 3 = 5 15 ÷ 5 = 3

Page 33: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Division - Arrays

12 ÷ 4 = 3 12 ÷ 3 = 4

2. Division - Arrays

Page 34: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

This helps to see the link

between division and grouping

3. Division – On a number line

12 ÷ 3 as ‘How many groups of 3

are in 12?’

0 1 2 3 4 5 6 7 8 9 10 11 12

Page 35: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

4 / 5. Division - Short Division

5 5 3 0 9

1 0 6 1 r 4 3

Start with one digit numbers

without remainders

Remind children of correct place value, that 96 is equal to 90 and6, but in short division, pose:

How many 3’s in 9? = 3

Page 36: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

5/6 . Division – Chunking

7 9 2- 3 6 0 4 3 2 - 3 6 0 0 7 2- 0 7 2 0 0

3 6 3 6 x 10 = 3 6 0

3 6 x 10 = 3 6 0

3 6 x 2 = 7 2

3 1

2 2 Circle the groups of 36 you have

‘chunked’ off the total.

Keep chunking until there is less than

36 left

Page 37: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Calculation Policy

This policy aims to clearly show strategies for calculating whilst meeting the expectations set out in the New Curriculum 2014. The policy is for use of all pupils, parents and staff in the Westfield community.

The strategies have been organised to show the progression from early calculation methods such as counting through to written methods involving decimals. The age expectations have been added to the calculations as a guide of where children should be working however decisions about when to progress should be based on the security of pupils understanding and their readiness to progress to the next stage. Pupils who grasp concepts rapidly should be challenged through being offered rich and sophisticated problems before any acceleration through newcontent. It is important that any type of calculation is given a real life context or problem solving approach to help build children's understanding of the purpose of calculation, and to help them recognise when to use certain operations and methods when faced with problems. This must be a priority within calculation lessons.

The Maths department will be offering Maths support for parents. Please contact the office for more information.

Page 38: Choosing a methodAddition methodsSubtraction methodsMultiplication methodsDivision methodsAbout this policy

Westfield Middle School

Visual Calculation Policy