Transcript Calculating - Western Primary School

Calculations in mathematics
Things are different now!
addition
Year 3
Partitioning method is used – for example
37 + 24 = 61
30 + 20 = 50
7 + 4 = 11
Addition
Year 4
Partitioning used for
increasingly large
numbers –eg
2417 + 3524 = 5941
2000 + 3000 = 5000
400 + 500 = 900
10 + 20 = 30
7+4
= 11
Year 4 continued
Vertical layout
introduced – eg
47+
76
110
13
123
368+
493
700
150
11
861
Addition
Year 5 & Year 6
As for year 4 but extended to include
decimals with partitioning – eg
7.6 + 5.8 = 13.4
7 + 5 = 12
0.6 + 0.8 = 1.4
Addition
Y6
More able children introduced to compact and efficient
method at the appropriate time – eg
1 7 9+
21 31 6
4 1 5
2 1 .7+
2 21 . 5
4 4 . 2
Subtraction
Year 3
Empty number line method is used – eg
95 - 33 = 62
7
50
5
33______________________________95
40
90
Subtraction
Years 4 – 6
The empty number line
continues to be used in these
year groups.
The children are encouraged
to develop increasingly refined
and efficient methods of using
the number line.
Subtraction
Year 6
Compact and efficient method introduced at appropriate
time for more able children – eg
6
4 7 16 –
1 3 9
3 3 7
6
5 7 . 12 3 4 . 5
2 2 . 7
Multiplication
Year 3
Arrays are used to develop understanding.
Children begin to use partitioning – eg
16 x 5 = 80
10 x 5 = 50
6 x 5 = 30
Multiplication
Year 4
Children continue to partition but grid method is
introduced – eg
6 x 32 = 192
X 30
6 180
2
12
Multiplication
Years 5 & 6
Grid method used with larger numbers and
decimals – eg
27 x 15 = 405
X 20
1.23 x 45 = 55.35
7
X 1
10 200
70 = 270
40 40
5
35 = 135
100
405
5
5
0.2
0.03
8
1.2
49.2
1
0.15
6.15
55.35
Multiplication
More compact method for grid introduced where
appropriate:
26 x 37
20 x 30 = 600
20 x 7 = 140
6 x 30 = 180
6 x 7 = 42
962
Multiplication
Y6
Compact and efficient method introduced when
appropriate for more able children – eg
3 2x
1 6
1 9 2
2
2
4
41 8
5 2
4x
2
8
0
8
4.8x
2 3
14 . 4
Division
Year 3 and 4
Chunking method used along with visual model
including remainders – eg
16 ÷ 4 = 4
36 ÷ 10 = 3 Rem 6
….
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Division
Years 4, 5 & 6
These methods can also be used with a number
line – eg
120 ÷ 9 = 13 rem 3
0____________________________90_____117__120
10x9
3x9
Division
Year 4, 5 & 6
The concept of chunking is still used but
method becomes numerical rather than
pictorial. Several strategies are used, all
of which rely on good knowledge of times
tables!
93 ÷ 6 = 15 rem 3 (16.5)
I know that 10 x 6 = 60
and 5 x 6 = 30
so 15 x 6 = 90
2. 265
÷ 13 = 20 rem 5
13 265
130 (10 x 13)
135 130 (10 x 13)
5
Useful websites
www.supermathsworld.com
Outer space-related activities on wide range of topics – annoying music though!
www.educationcity.com
Log-in: 815western
Password: school
Go to ‘Curriculum Map’
Maths
Choose year group then specific maths area
www.bbc.co.uk/schoolradio/maths/mathschallenge.shtml
Download radio programmes containing a variety of mental maths questions
www.subtangent.com
More able children – investigative challenges
nrich.maths.org/public
Go to ‘Stage 1 and 2’ down left-hand side for the latest mathematical challenges, graded
by difficulty with stars.
woodlands-junior.kent.sch.uk/maths
Allsorts of interactive activities. Well indexed.