Longfield Primary School
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Transcript Longfield Primary School
Maths Workshop for Year 2 Parents and Carers
14th January 2016
What do you understand by:
Multiplication?
Division?
What vocabulary can you think of that applies to each
of them?
What equipment, pictures or images can you think of
that might help children when starting multiplication
and division?
X
repeated addition eg 5 x 3 is the same as
(equals) 3 + 3 + 3 + 3 + 3
times
lots of
groups of
multiplied by
multiply
times tables
double
÷
Repeated subtraction
eg 20 ÷5 = 20 – 5 – 5 – 5 - 5
Divide
Divided by
Share
Share equally
Groups
Lots
Halve
Children need to know:
Each multiplication table from
0 x 2 to 12 x 2
0 x 5 to 12 x 5
0 x 10 to 12 x 10
They need to be able to count in 2s, 5s and 10s, forwards and backwards –
at least to the end of that table, and ideally to 100 for 2 and 5.
They need to know facts such as 2 more than 14, 5 less than 25.
They also need to be able to answer questions quickly such as ‘What is 10
times 5?’ ‘Twelve lots of 10?’ ‘How many groups of 2 in 22?’ How many
fives in 45?
These are multiplication and division facts.
Write the answers:
8 times 10?
How many 2s in 18?
What are nine groups of five?
Sixteen is how many groups of two?
What is 8 multiplied by 5?
Divide 120 by 10.
Seven twos are ... ?
How many 10s in 50?
Children need to know whether a number is even or odd
to know what will happen when it is multiplied or
divided.
They need to know that even numbers will ...
end in 2, 4, 6, 8 or 0.
And odd numbers will ...
end in 1, 3, 5, 7 or 9.
This means multiplication statements for up to 12 x.
For example:
10 x 5 = 50 5 x 10 = 50
50÷ 10 = 5
50 ÷ 5 = 10
Try this!
Write the multiplication and corresponding division statements for:
8 and 5
6 and 10
8 x 5 = 40
5 x 8 = 40
6 x 10 = 60 10 x 6 = 60
40 ÷ 5 = 8 40 ÷ 8 = 5
60 ÷ 6 = 10 60 ÷ 10 = 6
Use x ÷ = to make these correct
6 5 30
6 x 5 = 30
8 ÷ 2 = 4 or 8 = 2 x 4
824
100 10 10 100 = 10 x 10 or 100 ÷ 10 = 10
Use 5 8 and 40 to make these correct
x =
8 x 5 = 40 or 5 x 8 = 40
÷ =
40 ÷ 8 = 5 or 40 ÷ 5 = 8
Commutative – a tricky word that children in Year 2 are
not expected to know – but they do need to understand
the idea behind it.
Addition and multiplication are commutative operations. This
means that for these operations the numbers can be added or
multiplied in any order and the answer will still be the same.
So 8 + 4 = 12 is the same as 4 + 8 = 12
And 8 x 5 gives the same answer as 5 x 8.
But subtraction and division are not commutative.
8 – 4 (= 4) is not the same as 4 – 8. (= -4)
And 40 ÷ 5 (= 8) is not the same as 5 ÷ 40 (= 0.125)
Children need to be taught this – they don’t automatically know or
recognise it, and often won’t notice or realise that they have written
the calculation the wrong way round.
Try these calculations for yourself just to check
what happens...
8 x 10 =
10 x 8 =
80
50 ÷10 =
10 ÷ 50 =
5
80
0.2
Problems – word problems or problems involving
reasoning or working things out from known facts.
Contexts might mean using multiplication and
division in other subjects, such as science, PE or
history.
Could be problems involving measures,
mass/weight, height/length, data, money.
The multiplications
for this array would
be 4 x 2 = 8
Oh dear! The
naughty pup has
chewed some of
Sam’s stamps. How
many stamps did
Sam have to start
with?
What is the multiplication sentence for this array?
2 + 2 + 2 + 2 + 2 = 10
5 groups of 2 or 5 x 2 = 10
2 multiplied by 5 or 5 multiplied
by 2
5 pairs
5 hops of 2
5 + 5 + 5 + 5 + 5 + 5 = 30
6 groups of 5 or 6 x 5 = 30
5 multiplied by 6 or 6 multiplied
by 5
6 groups of 5
6 hops of 5
10p + 10p + 10p +10p + 10p = 50p
5 times 10p = 50p
5 hops of 10p
5 x 10p = 50p
Multiplication and division are inverse operations.
This means they are the reverse of each other.
So an answer can always be checked by carrying
out the calculation the other way round.
8 x 10 = 80
So, 80 ÷ 10 = 8
or 80 ÷ 8 = 10
One for you, and you and you and you and me.
Keep going until they have all been used up. If there are
any objects left over they are called the ‘remainder’.
You can use any objects to
represent the cakes, but ask a
child to do this practically first –
using concrete objects helps
make the connection between
real objects and the symbols we
use in maths.
Keep taking out
groups of the same
number.
How many groups
are there? Any left
over that won’t
make another
group of the same
number are the
remainder.
24 ÷ 2 =
stickers
8x5=
How you can help at home
• Notice numbers all around us
• Practice counting up and back from different starting
points, in 1s then in steps of different sizes
• Learn number bonds, number doubles and times tables
• Practice telling the time, knowing days of week,
months of the year, noticing the date
• Familiarisation with coins, simple shopping bills, value
for money offers in shops
• Measures – g, kg, ml, l, cm, m
• Playing board games – such as Yahtzee, Monopoly,
snakes and ladders, card games, dominoes.
http://www.bbc.co.uk/bitesize/ks1/maths/
http://www.topmarks.co.uk/maths-games/5-7years/multiplication-and-division
http://www.maths-games.org/times-tablesgames.html
http://www.maths-games.org/fraction-games.html
http://primarygamesarena.com/Key-Stage-1