WELCOME TO WEST HOATHLY CE PRIMARY SCHOOLS MATHS EVENING!

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WELCOME TO WEST HOATHLY

CE PRIMARY SCHOOL’S MATHS

EVENING!

By the age of 11 they should : • Have an understanding of place value• Know number facts• Use number facts in calculations• Use mental and written methods• Use a calculator• Explain their methods and reasoning• Answers to calculations are feasible

What can a numerate child do?

The aim is for children to do mathematics in their heads, and if the numbers are too large, to use pencil and paper to avoid losing track.

To do this children need to learn quick and efficient methods, including appropriate written methods.

Our Aim

BEGINNER: Begin to relate subtraction to ‘taking away’. In practical activities and discussion begin

to use the vocabulary involved in subtracting.

• Everyday activities are used in class to encourage the practical use of subtraction and the appropriate language, such as registration, snack time and giving out of resources. Children need to work out how many extra they have and take them away.

• We use a lot of songs to introduce the language and concept of ‘taking away’, such as ‘5 Currant buns in a bakers shop’. A wide range of play activities such as farm animals, cars, bricks, and beads are used to support children in early subtraction skills.

• At home these experiences can be developed through practical activities such as shopping, laying the table and cooking using the language ‘too many’, ‘take away’, ‘subtract’ and ‘how many are left’

TARGET 1: Using practical apparatus count how many are left within 5

• We start by using our most practical resource…….our fingers! (Five fingers take away 1 finger = 4 fingers).

• This can be developed by using any objects that the child is interested in such as cars, bricks and beads etc.

• Unifix or Multilink cubes are a very helpful resource as colours can be used to demonstrate different amounts.

TARGET 2: To use number lines to solve and record subtraction calculations.

• Use a number line to make ‘jumps’ back wards to find the answer.

• 8-2 = 6.

• Check that the answer is always smaller than the starting number. (This helps them jump the right way on a number line and helps them to learn to check their calculations early on)

TARGET 3: UNDERSTANDING SUBTRACTION AS

‘FINDING THE DIFFERENCE’.

• How would you find the answer to

82 – 79?

YEAR 1: Find a small difference by counting up.

For example: 4 – 2 =

You could hold the 2 in your head and count on to the 4, thus finding the difference.

YEAR 1: Find a small difference by counting up.

YEAR 2: Recognise that when finding the difference between two numbers that

are close together, it is easier to count up from the smaller to the larger number, rather

than counting back.

TARGET 4: USING MARKED

TARGET 4: USING MARKED NUMBER LINES TO

RECORD SUBTRACTION CALCULATIONS BY

COUNTING ON:

USING A NUMBER LINE TO DO THIS:

7 10 12

+ 3 + 2

11 20 21

+ 9 + 1

12 - 7

21 - 11

TARGET 5/6: USING AN EMPTY NUMBER LINE TO RECORD SUBTRACTION

OF LARGER NUMBERS BY COUNTING ON FROM THE

SMALLER NUMBER TO THE LARGER NUMBER

(COMPLIMENTARY ADDITION).

USING AN EMPTY NUMBER LINE TO DO THIS:

65 - 38

65 – 38 =

AND THIS…

242 - 165

242 – 165 =

Silent Subtraction Game!

Each person has one card with a calculation on it.  They have a short time to work out their own calculation, then they all have to stand in a line in the correct order, highest answer to lowest answer.  So not only do they have to work out their own answer, they have to work out lots of others too! 

Learning written methods is not our ultimate aim.

Maths teaching today aims to develop children’s mental strategies to support written methods.

•Can I do this in my head?•Can I do this in my head using drawings or jottings?•Do I need to use a written method?•Do I need a calculator?

TARGET 7

Use refined methods of complimentary addition to subtract whole numbers.

86 - 29

345 – 268Have a go!

Target 8/9: Extend to decimals

75.6 – 28.2

92.46 – 58.7Have a go!

Target 9/10: To use compact method of decomposition to

subtract integers and decimals.

We do not teach children subtraction by decomposition until they are very

confident using complimentary addition, as many children make errors using

decomposition

Mistakes children make

4500 4500 -3768 - 3768 1200 1288

Can you see where the mistakes have been made?

900000 - 3654

Some pupils will attempt subtraction calculations using the formal written method, failing to recognise that it would be more efficient to calculate the answer mentally.

Partitioning leading to a compact method

Have a go!

6500

- 1837

How can you help?

Talk about how you do maths

Give praise and encouragement

Be positive

Ask your child to explain

Make sure maths is fun!

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