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Transcript
Northway Community Primary School
Written Calculation Policy 2014
MULTIPLICATION
Place value skills
needed
Method
Expectation
STAGE 1: Practical repeated addition (end of EYFS)




Talk about
groups of
objects
Talk about
sharing
Use
appropriate
vocabulary –
groups of, lots
of.
Make sets of
equal objects
‘We are making gingerbread men. How many
sweeties will we need for the eyes?
1 2
\ /
3 4
\ /
5 6
\ /
Link to practical
problem solving
activities involving
equal sets of
groups/role play
situations
e.g. How many socks on 2 children? Let’s
count them. (Stick post-its for numbers on
each leg.)
STAGE 2: Practical and pictorial arrays towards grid (end of KS1)








Understand
the concept of
equal grouping
Doubles to 15
Knowing X
means groups
of
Understand
double means
x2.
Count up and
back in 2s 3s
5s 10s
Recognise and
talk about an
array
Jump on equal
steps along a
numbered
number line
Count on using
Counting in 2s 3s 5s 10s
3 groups of 2 = 6
Repeated addition 2+2+2+2+2 =10
5 x 2 = 10
Chanting
2x table  2 x 5 = 10
3x table
5x table
10x table
Know that multiplication can be done in any
Represent repeated
addition and arrays as
multiplication.
Use practical and
informal written
methods and related
vocabulary to support
multiplication
Northway Community Primary School
Written Calculation Policy 2014
a number line

order 2x5 = 5x2
Arrays and multiplication as repeated
addition.
Number patterns –
jumping in 3s and 4s







Word problems – There are 6 boxes. Each
box has 10 pencils. How many pencils are
there?
STAGE 3: Grid method and short expanded column method (end of LJ)
Know the result
Use practical and
17
of X by 0 and 1
informal written
4x
17 x 4 =
Understand
methods to multiply
place value (can
two digit numbers by a
partition TU)
X 10
7
one digit number (13 X
Know by heart
4) – target X tables
2,5,10 X facts
4 40 28 Lock in the zero
Understand that
and related
multiplication is the
division
inverse of division.
Understand zero
Derive and record
as a place holder
= 40 + 28 = 68
related X sentences.
Know how to X 2
digit numbers by
Missing numbers X =
376 x 4 =
10
TU X U (teen numbers
Double 2 digit
eg 19 x 4)
numbers
(multiples of 5
and 10)
Know the result
of a
multiplication
will be bigger
and is called the
product.
X 300 70 6
4 1200 280 24
1200
280
24 +
1504
Develop and use written
Northway Community Primary School
Written Calculation Policy 2014





Multiply 2 and
3 digit numbers
mentally by 10
and 100
Know by heart
all
multiplication
facts up to 12
x 12.
Use known
facts to
calculate
unknown
Explain mental
X strategies
orally
Add 2/3 digit
numbers
17
14 x
X
10
4
10
100
40
17 x 14 =
7
70
28
methods to record,
support and explain
multiplication up to
HTU x U.
170 +
68
238
Repeat with HTU x TU
Multiply the units first.
24
3x
1 2
60
(3 x 4)
(3 x 20)
72
1 2 4
3x
1 2
6 0
3 0 0
2 7 2
( 3 x 4)
(3 x 20)
(3 x 100)
STAGE 4: Short expanded column (multiplying by units only) (end of UJ)

As above
24
3 x
7 2
1
Progress to:
1241
3x
3723
1
Northway Community Primary School
Written Calculation Policy 2014
STAGE 5: Long column





Understand
place value of
decimals to 2
places
Know by heart
all X facts to
12 x 12
Relate 8 X 7 =
56 to 8 X 0.7 =
5.6
X 2/3 digit
multiples of 10
mentally eg 20
X 50
Use column
addition
Refine and use
efficient written
methods to multiply
HTU X U
HTU x TU
THTU X TU
In the examples given, it is also correct to multiply
starting with the tens digit (ie multiplying by the most
significant digit first)

Mentally multiply
decimals by
multiplying the
decimal number
by 10 to make a
whole number,
then dividing the
answer by 10.
Use efficient written
methods to multiply
integers and decimals
by a one digit integer
and to multiply:
HTU X TU
1.7 x 4 =
X
1
0.7
4
4
2.8
(7 x 4) ÷ 10
= 4 + 2.8 = 6.8
4.92 x 3
x
4
0.9
0.02
3
12
2.7
0.06
12
+ 2.7
+ 0.06
14.76