Our Key Strategies for Addition and Subtraction
Strategy
|
Example
|
Place Value (Addition)
Splitting the numbers into
parts
|
234 + 657 = 891
200 + 600 = 800
30 + 50 = 80 4 + 7 = 11
800 + 80 + 11 = 891
|
Place Value (Subtraction)
Splitting the numbers into
parts using the big number first
|
89 – 36 = 53
89 – 30 = 59
59 – 6 = 53
|
Rounding and Compensating (Addition)
Adding a little bit on to
make a tidy number then taking that little bit off at the end
|
145 + 28 = 173
28 +
2 = 30
145 + 30 = 175
175 – 2 = 173
|
Rounding and Compensating
(Subtraction)
Adding a little bit on to
make a tidy number then adding that little bit more on at the end to make up for
taking too much off
|
175 – 99 = 75
99 + 1 = 100
175 – 100 = 75
75 +
1 = 75
|
Equal Additions (Subtraction)
Adding a small bit to the second number to make it a tidy number,
then adding the same amount to the other number to adjust the adding
|
376 – 48 =
48 + 2 = 50 376 + 2 = 378
378 – 50 = 328
|
Reversibility (Subtraction)
Making a subtraction problem into an addition problem to make it
easier to solve
|
33 – 26 = 7
26 + _ = 33
26 + 7 = 33
|
Multiplication Strategies I can use:
Strategy
|
Example
|
Using my 5 times tables to work out
6,7 and 8 times tables
|
8 × 7 =
8 × 5 = 40
8 × 2 = 16
40 + 16 = 56
|
Place Value (Basic Mult)
Splitting the numbers into
parts
|
24 × 5 =
20 × 5 = 100
4 × 5 = 20
100 + 20 = 120
|
Place Value (Harder Mult)
Splitting the numbers into parts
|
35 × 63 =
30 × 60 = 1800
30 × 3 = 90
5 × 60 = 300
5 × 3 = 15
1800 + 300 = 2100 + 90 = 2190 + 15 =
2205
|
Rounding and Compensating (Mult)
Adding more groups on to make
a tidy number then taking off the groups at the end
|
37 × 6 =
(add 3 groups on) 40 × 6 = 240
240 – (3×6=18) = 222
|
Doubling and Halving (Mult)
You look for one of the
numbers that when doubled or halved will give you an easy problem to solve.
|
42 × 20 =
Halve 20 = 10
Double 42 = 84
So now solve 84 × 10 = 840
|
Division Strategies I can use:
Strategy
|
Example
|
Using my times tables to work out basic division facts
|
8 × 7 = 56
so
56 ÷ 8 = 7
|
Reversibility
Change the division problem to a multiplication problem
|
42 ÷ 7 =
7 × ____ = 42
so 7 × 6 = 42
|
Place Value
Splitting the numbers into parts
|
96 ÷ 8 =
We think of our 8 times (times by 10) tables to help us split the numbers e.g. 80, 160.
80 ÷ 8 = 10
Then we work out how much is left over 96 - 80 = 16 so
16 ÷ 8 = 2
10 + 2 = 12
|
Halving and halving
Halving both the numbers until you can find ÷an easy solution.
|
112 ÷ 8 = ? 112 ÷ 2 = 56 8 ÷ 2 = 4
56 ÷ 4 = ? 56 ÷ 2 = 28 4 ÷ 2 = 2
28 ÷ 2 = 14
|
Rounding and Compensating
Adding more groups on to make a tidy number then taking off the groups at the end
|
68 ÷ 4 =
we round it up to 80 as that is in the 4 times tables.
80 ÷ 4 = 20
20 - (12÷4= 3) = 20-3 = 17
|
Long Division
|  |
http://www.mathematicshed.com/index.html - good engaging maths site
These are some good measurement games to play:
http://www.bgfl.org/custom/resources_ftp/client_ftp/ks2/maths/perimeter_and_area/index.html
http://www.mathplayground.com/area_perimeter.html
http://www.mathplayground.com/PartyDesigner/PartyDesigner.html
http://mrnussbaum.com/zoo-play/
http://mathszone.co.uk/measuring/area-and-perimeter/
http://www.sheppardsoftware.com/mathgames/geometry/shapeshoot/PerimeterShapesShoot.html
http://www.funbrain.com/poly/
http://www.maths-games.org/time-games.html
http://www.topmarks.co.uk/maths-games/7-11-years/measures
These are some good Geometry Games for you to play:
Click on these links for games for you to practice your multiplication
Grand Prix Game
Cone Crazy Game
Flying High Game
Penguin Jump Game
Super Stars Game
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