Ontario Curriculum MATHEMATICS
3rd
4th
5th
Number Talks
2016 © All Sorts of Math
Strategies Posters
3rd
ADDITION STRATEGY
Doubles
The Doubles help with the Near Doubles.
25 + 25
4th
4th
ADDITION STRATEGY
Doubles
The Doubles help with the Near Doubles.
250 + 250
5th
3rd
ADDITION STRATEGY
Near Doubles
The Doubles help with the Near Doubles.
25 + 26
25 + 26 = 25 + (25 + 1)
25
25
25
+
26
1
4th
4th
ADDITION STRATEGY
Near Doubles
The Doubles help with the Near Doubles.
250 + 260
250 + 260 = 250 + (250 + 10)
250
250
250
+
260
10
5th
3rd
4th
ADDITION STRATEGY
Add Up in Chunks
Keeping one addend whole, add the second addend in friendly chunks.
23 + 12
+10
23
+2
33 35
4th
5th
ADDITION STRATEGY
Add Up in Chunks
Keeping one addend whole, add the second addend in friendly chunks.
209 + 124
+100
209
+20 +1 +3
309
329 330 333
3rd
ADDITION STRATEGY
Place Value
Decompose and add by the place value.
21 + 14
20
1
10
4
20 + 10 = 30
1+4=5
30 + 5 = 35
4th
4th
ADDITION STRATEGY
Place Value
Decompose and add by the place value.
124 + 235
100 + 200 = 300
20 + 30 = 50
4+5=9
300 + 50 + 9 = 359
5th
3rd
4th
ADDITION STRATEGY
Compensation
Make friendlier numbers by removing from one addend, then adding
the same amount to the other addend.
17 + 19
–1
+1
16 + 20 = 36
4th
ADDITION STRATEGY
Compensation
Make friendlier numbers by removing from one addend, then adding
the same amount to the other addend.
127 + 119
–1
+1
126 + 120 = 246
5th
3rd
ADDITION STRATEGY
4th
Make Friendly Numbers
Make a friendly number by decomposing another addend.
18 + 6
2
4
18 + 2 = 20
20 + 4 = 24
4th
ADDITION STRATEGY
5th
Make Friendly Numbers
Make a friendly number by decomposing another addend.
116 + 118
4
2
118 + 2 = 120
120 + 114 = 234
3rd
ADDITION STRATEGY
Make a Ten
Make a ten by decomposing another addend.
18 + 6
2
4
10 + (8 + 2) = 20
20 + 4 = 24
4th
4th
ADDITION STRATEGY
Make a Ten
Make a ten by decomposing another addend.
138 + 116
2
4
(130 + 8) + (110 + 2 + 4)
130 + 110 + (8 + 2) + 4
240 + 10 + 4
250 + 4 = 254
5th
3rd
4th
SUBTRACTION STRATEGY
Add Up
Start with the subtrahend, add up in friendly chunks to the minuend.
50 – 39 = 11
11
+1
39 40
+10
50
4th
5th
SUBTRACTION STRATEGY
Add Up
Start with the subtrahend, add up in friendly chunks to the minuend.
123 – 69 = 54
54
+1
69 70
+30
+23
100
123
3rd
SUBTRACTION STRATEGY
Removal
Start with the minuend, remove the subtrahend in friendly chunks.
22 – 8 = 14
–8
–6
14
–2
20
22
4th
4th
SUBTRACTION STRATEGY
Removal
Start with the minuend, remove the subtrahend in friendly chunks.
122 – 28 = 94
– 28
–6
94 100
–22
122
5th
3rd
4th
SUBTRACTION STRATEGY
Constant Difference
Changing both the minuend and subtrahend by the same amount.
53 – 29 = 54 – 30
54 – 30 = 24
24
29 30
53 54
4th
5th
SUBTRACTION STRATEGY
Constant Difference
Changing both the minuend and subtrahend by the same amount.
117 – 49 = 118 – 50
118 – 50 = 68
68
49 50
117 118
3rd
SUBTRACTION STRATEGY
4th
Adjust One Number
Adjusting one number to make a friendlier problem.
43 – 29
+1
43 – 30 = 13
13 + 1 = 14
3rd
SUBTRACTION STRATEGY
4th
Adjust One Number
Adjusting one number to make a friendlier problem.
43 – 29
+1
43 – 30 = 13
13 + 1 = 14
+1
13 14
–30
43
4th
SUBTRACTION STRATEGY
5th
Adjust One Number
Adjusting one number to make a friendlier problem.
103 – 59
+1
103 – 60 = 43
43 + 1 = 44
4th
SUBTRACTION STRATEGY
5th
Adjust One Number
Adjusting one number to make a friendlier problem.
103 – 59
+1
103 – 60 = 43
43 + 1 = 44
+1
43 44
–60
103
3rd
4th
SUBTRACTION STRATEGY
Place Value
Decompose and subtract by the place value
75 – 38
70 – 30 = 40
5–8=–3
40 – 3 = 37
4th
5th
SUBTRACTION STRATEGY
Place Value
Decompose and subtract by the place value
245 – 168
200 – 100 = 100
40 – 60 = – 20
5–8=–3
100 – 20 – 3 = 77