Download Learning to Calculate in Key Stage 1 addition subtraction

Learning to Calculate in Key Stage 1
Year
1
addition
subtraction
multiplication
division
Combine sets to make a
total, e.g.
‘I have 5 pennies and 3
pennies. How many have I
altogether?’
Counting on:
Understand the image of
subtraction as ‘take away’
and also as ‘difference’:
11 – 7 = 4
Count on or back in 2s and
10s. Begin to count in 5s.
Begin to understand division as
grouping or sharing.
Use a number line to do
this, e.g.
6 ÷ 2 can mean ‘share 6 objects
equally among 2 people’, or
‘how many groups of 2 are
there in 6?’ (e.g. jumps on a
number line.)
Five….six,
seven, eight
1 2 3 4 5 6 7 8 9 10 11
‘Take away’
5 10 15 20 25 30 35
Counting in 5s
11 – 7 = 4
Use a number line to count
on in ones:
3+2=5
+1 +1
0
1 2 3 4 5 6 7
1 2 3 4 5 6 7 8 9 10 11
‘Difference’
Add 9 to single digit
numbers by adding 10 then
subtracting 1, e.g.
6 + 9 = 6 + 10 – 1.
Add or subtract a pair of
numbers mentally by bridging
through 10, e.g.
22 – 7 = 22 – 2(20) – 5 = 15
Count along using 2ps, 5ps
or 10ps.
E.g. I have 12 pencils to put
equally in 3 pots. How many
pencils will be in each pot?
(Sharing)
0
2p
4p
6p
There are 12 apples. How many
bags of 3 apples can be filled?
11 12 13 14 15 16 17 18 19 20 21 22
Relies on seeing 7 as 2 + 5.
(Grouping)
Year
2
addition
subtraction
multiplication
Know what each digit in a
two-digit number
represents, e.g. 27 is 2
tens and 7 ones.
Know by heart all addition
and subtraction facts for all
numbers up to and including
10.
Use partition when adding:
12 + 23 = 10 + 2 + 20 + 3
= 30 + 5
= 35
When working with a number
line, begin to see the
counting on or back in larger
jumps.
Understand multiplication as As above until secure.
repeated addition, e.g.
5x3=5+5+5
Number lines to secure
grouping.
or as a way of describing an
array, e.g.
12÷2=
Work towards keeping the
first number whole, and
partitioning the second
number:
34 + 23 = 34 + 20 + 3
= 54 + 3
= 57
Begin to understand the
relationship between
addition and subtraction, e.g.
if 15 + 4 = 19, then
19 - 4 = 15, and
4 + 15 = 19, so
19 – 15 = 4.
Begin to use a number line
to start with the largest
number and count on:
Decide which strategy to use
when subtracting. If the
numbers are close together,
count up, e.g. 22 – 18 = 4 (by
counting up from 18)
+10
34
+10
44
+1 +1 +1
54 55 56 57
Move towards adding the
tens in one jump and the
ones in one jump.
If numbers are further
apart, take away, e.g.
77 – 5 = 72 (by counting back
5 from 77).
division
5 x 3 = 5, three times.
Using a bead bar: 5 x 3
5
5
5
And on a number line:
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Understand that 5 x 3 is
the same value as 3 x 5.
-2
0
-2
2
-2 - 2 -2 -2
4
6 8
10
12