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

Addition and Subtraction Strategy video links made by the children:
Decimal Place Value video links:
http://www.educreations.com/lesson/view/placevalueeasymultiplication/23151695/?ref=app
Perimeter and Area video links:
http://www.educreations.com/lesson/view/areaofirregularshapes/22962511/?ref=app
Multiplication Strategy video links:
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) = 203 = 17

Long Division

http://www.educreations.com/lesson/view/678timestablesfromknowntimestables/23151903/?ref=app
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/zooplay/
http://mathszone.co.uk/measuring/areaandperimeter/
http://www.sheppardsoftware.com/mathgames/geometry/shapeshoot/PerimeterShapesShoot.html
http://www.funbrain.com/poly/
http://www.mathsgames.org/timegames.html
http://www.topmarks.co.uk/mathsgames/711years/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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