Transcript Can I do this in my head?

Mental Maths
Parent Workshop
How mental maths is taught in
school and ways in which you can
support your child at home.
It’s not just times-tables!
How has mathematics changed?
• Daily mathematics lesson;
• Emphasis on mental calculations;
• Interactive whole class and group
teaching;
• Enjoyable practical approaches including
games, group work, problem solving;
• Mathematics with understanding – not just
learning a method but understanding why
a method works too
What can a numerate child do?

calculate accurately and efficiently, both
mentally and on paper, using a range
of strategies

explain their methods and reasoning
using correct mathematical terms

judge whether their answers are
reasonable and have strategies for
checking them where necessary
Learning written methods is not
the ultimate aim.
 Mathematics is foremost an activity of the
mind, and written calculations are an aid
to that mental activity.
 The Numeracy Strategy aims to develop
children’s mental strategies and then
written methods that derive from and
support mental methods.
We want children to ask
themselves:
1
Can I do this
in my head?
2
Can I do this in my
head using
drawings
or jottings?
3
Do I need to use an
expanded/ compact
written method?
4
Do I need a
calculator? (More
able Year 4s and
Y5 and Y6)
Addition and Subtraction
• Inverse
• Relate known addition facts to subtraction facts.
• By the end of Year 2 children should know
most of the facts for single digit numbers
up to 9+9=18
+3
+2
8 + 5 = 13
5 + 8 = 13
13 – 8 = 5
13 – 5 = 8
8
13
10
-5
5
-3
10
13
Key Facts
Year 1:
• Pairs of numbers that total 10 and some stories
up to 10 E.g. 2 + 5 = 7, 5 +  = 9 , 6 – 4 = 2
• Doubles up to totals of 10 e.g 5+5
Year 2
• Pairs of numbers that total 20 and related
subtraction facts
• Relate pairs to ten to ten to know pairs of tens
that total 100 e.g. 60 + 40 = 100
• Most of the facts for single digit numbers up to
9+9=18
• Doubles up to totals of 20
Key Facts
Year 3
• Pairs of numbers that total 20 and related
subtraction facts
• Relate pairs to ten in order to know pairs of tens
that total 100 e.g. 60 + 40 = 100
• Know all of the addition facts for totals up to 18
E.g.7 + 5 = 12, 9 +  = 18
• I know all subtraction facts for numbers up to 18
in my head. Eg 13 – 6 = , 17 –  = 12
• know lots of pairs of two-digit numbers that total
100, eg 68 + 32 = 100
• add 2 two-digit numbers together mentally
Key Facts
Year 4
• Relate bonds to ten and 100 to work bonds
to 1000
• Efficiently and subtract numbers on an
empty numberline including decimal
numbers as money or measures and time
intervals
• mentally subtract a two digit number from
another two digit number by counting on to
find the difference
A number line is
just a ‘picture’ of
how we work out
some calculations
in our heads!
20-6
14
15
20
78 - 12
66
66
78
68
76
78
74 - 57
57
57
60
74
67
74
Tenzin and Sarah Y4
• 3001 – 2998 = ?
Subtraction with decimals on a
number line
Have a go!
• 22 – 5 =
• 145 – 94 =
• The bus is due to arrive at 7.35am but
is 46 minutes late. What time does it
arrive?
• Sally wants to buy a CD that costs
£15.60. She only has £13.45. How
much more money does Sally need to
buy the CD?
Multiplication and Division
Count repeated groups
of the same size
Separate a group
in different ways
Number rhymes,
story props,
Handa’s surprise.
Share objects into
equal groups
Sharing and looking at
remainders,
number lines.
Multiplication and Division
• Inverse
• Relate known multiplication facts to division
facts.
• By the end of Year 2 children should know 2x, 5x
and 10x tables and related division facts
• By the end of Year 3 children should know 2x,
5x,10x , 3x and 4x tables and related division
facts
• By the end of Year 4 children should know 2x,
5x,10x, 3x, 4x, 6x and 7x tables and related
division facts
• By the end of Year 5 children should know all the
times-tables up to 10x10 and related division
facts
How are times-tables taught?
•
•
•
•
•
•
•
Counting on and back
Chanting
Games
ICT / internet games
Independent and group work
Times-table tests in class
Homework
Real Life Multiplication and Division
Mental calculations for Y5 and 6
First using partitioning
93 ÷ 7 =
First we partition the 93 into a convenient
multiple of 7 + the rest
93
70
10
+
+
23
3r2
= 13 r 2
First using partitioning
84 ÷ 7 =
First we partition the 84 into a convenient
multiple of 7 + the rest
84
70
10
+
+
14
2
= 12
Counting sequences to help with
times-tables Y4
Counting sequences to help with
times-tables Y6
MoT
•M
aster
•of
•T
imes-Tables
Mini MoT
x2, x5, x10
Middle MoT
x3, x4, x6
Master MoT
x7, x8, x9
How do we know when a child
knows a times-table?
How can you help?
Talk about
how you
do maths
Give praise and
encouragement
Use the My Maths
website to help both you
and your child
Be positive
Ask your
child to
explain
Make sure maths is fun!
My Maths
Lots of support and guidance is on
our school website.
• http://webfronter.com/walthamforest/stoneydown/index.shtml