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Subtraction
YEAR 1
YEAR 2
+ = signs and missing numbers
7–3 =□
7-□=4
□-3 =4
□-Δ=4
YEAR 3
- = signs and Missing Number Sentences
Continue using a range of equations as in Year 1 but with appropriate
numbers e.g.
25 – 8 = □
Δ - □ = 16
Extend to
14 + 5 = 20 - □
□= 7 - 3
4 =□- 3
4= 7 -□
4 =□–Δ
Mental Calculations
Understand the operation of subtraction (as ‘take away’, difference and
how many more to make.
- = signs and Missing Number Sentence
Continue using a range of equations as in year 2 but with appropriate
numbers.
Mental Calculations
Model thought process and jottings for mental maths as.
Find a small difference by counting up
e.g. 134 - 126
This can be modelled on an empty number line (see complementary
addition below). Start on 0, subtract the amount, what is left?
Mental Calculations
Find a small difference by counting up
Model thought process as: Take away the 39, what am I left with.
42 – 39 = 3
Use a completed number line or number track to solve subtraction. Both by
counting back and finding the difference for example 9 – 6.
+1
0
39
+2
40
+4
1
2
3
2
3
4
5
4
5
6
6
7 8
7
9
Subtract 9 or 11. Begin to add / subtract 19 or 21
Model thought process as:
35 - 9 = 26
8 9
e.g. 16 – 7
-1
6 7 8 9 10 11
-1
-1 -1 -1
12 13
26
78
-50
Written Calculations
Model use of landmark numbers and these four steps.
+1
9
Use known number facts and place value to subtract
97 – 25 = 72 is approximately 100 – 25 = 75
53 – 18 =
72
6 7
8
9
77
97
10 11 12 13 14 15 16 17
Leading through to bridging to 10 for more able pupils on a completed
number line.
+3
+6
9
7
29
28
-1
+1
134
35
10
14 15 16 17
+1 +1 +1 +1 +1 +1 +1
130
+1
25
9
-1
126
Subtract the nearest multiple of 10, then adjust
Continue as in Year 2 but with appropriate numbers.
e.g. 78 – 49 is the same as 78 – 50 +1
+1
Find the difference between numbers below 20 by counting on or back
on a printed number line.
8
42
0
1
+4
10
Start on 0.
Subtract 18
0
Bond
s to
ten
18
Count
in tens
20
Partitioning
50
53
-5
Written Calculation
Develop complements to 100
300 – 84 = 668
Start on 0.
Subtract 84
- 20
Bonds
to 100
Count in
100’s
16
0
Subtraction
84
100
300
YEAR 4
YEAR 5
+ = signs and Missing Number Sentences
Continue using a range of equations as in year 3 but with appropriate
numbers.
Mental Calculations
Model thought process and jottings for mental maths as.
Find a small difference by counting up
e.g. 5003 – 4996 = 7 Start on 0, subtract the amount, what is left?
When children are secure this step is not needed.
This can be modelled on an empty number line (see complementary
addition below)
+4
+3
YEAR 6
- = signs and missing numbers
Continue using a range of equations as in Year 4 but with appropriate numbers.
Mental Calculations
Model use of jottings to support calculations.
Mental Calculations
Model thought process and jottings for mental maths as:
Subtract the nearest multiple of 10 or 100, then adjust
Subtract the nearest multiple of 10, 100 or 1000, then adjust
Continues as in 2, 3 and 4 but with appropriate numbers
Continue as in year 2, 3, 4 and 5 but with appropriate numbers
Partitioning and counting back
e.g. 186 – 44 = which is 186 – 40 = 146 then 146 – 4 = 142
Partitioning and counting back
e.g. 186 – 44 = which is 186 – 40 = 146 then 146 – 4 = 142
7
Model use of landmark numbers
Model thought process.
6.1 – 2.4
0
4996
5000
- = signs and missing numbers
Continue using a range of equations as in Year 5 but with appropriate
numbers.
Use known number facts and place value to subtract
5003
0.5 – 0.31 = 0.19
0.09
3.7
+0.6
+3
+0.1
0.1
0.19
Partitioning and counting back
e.g. 86 – 44 = which is 86 – 40 = 46 then 46 – 4 = 142
2.4
3
6
6.1
0.31
0.4
0.5
Use known number facts and place value to subtract
92 – 25 = 67
67
72
92
6467 – 2684 = 3783
-5
- 20
Subtract the nearest multiple of 10, then adjust
Continue as in Year 3 but with appropriate numbers.
e.g. 276 – 39
+1
754 – 286 = 468
3783
468
276
-40
Written Calculations
Complementary addition. Start with number line at 0. Subtract the
amount, what is left? When children are secure this step is not needed.
3-digits – 2-digits
In the context of money
754 – 86 = 668
Bonds to
Count in
Partitioning
Subtract
100’s
100
amount
0
Compliments
to 100/1000
237
236
86
100
700
Written Calculations
4-digits – 4-digits Start with number line at 0
1 and 2 decimal places
Complementary addition
Written Calculations
Complementary addition. Start with number line at 0
3-digits – 3-digits
4-digits – 3-digits
754
286
Count in
100’s/1000’s
300
700
8006 – 2993 = 5013
+7
2993
754
5013
+5000
3000
Partitioning
+6
8000
8006
Compliments
to 100/1000
2684
3000
316
3000
+ 467
3000
700
70
13
3783
Partitioning
Count in
100’s/1000’
s
6000
6467