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St. Joseph’s Catholic Primary School Tuesday 15th October 2013

KS1 Mathematics Workshopled by KS1 Team

Miss Brown (Yr.1) Mrs Morrin (Yr.2) Mathematics Leader

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Aims of the Workshop

To explore the different mental strategies & written calculation methods for addition, subtraction, multiplication and division.

To see the progression and the development in the different calculation methods from

Year 1 on Year 2.

To share strategies with you today so you can support your child at home.

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Yr. 1 Addition –

Objectives: To relate addition to counting on. To recognise that addition can be done in

any order. To use concrete and pictorial methods to

support the addition of a one-digit number or a multiple of ten to a one or two digit number.

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Yr.1 – How to teach Addition at home

Methods/strategies: Combining two sets and counting all Put the larger number first and find the total

by counting on Use our fingers to count Use a number line to count on Record as an equation or a number sentence e.g.12 + 2 = 14

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Year 2 – Addition Objectives

Add or subtract mentally a one-digit number or a multiple of 10 to or from any two-digit number; use concrete and pictorial methods to add and subtract two-digit numbers.

Understand that subtraction is the inverse of addition and vice versa; use this to derive and record related addition and subtraction equations.

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Year 2 – How to teach Addition at home

Count on in tens and onesRecord as: 23 + 12 = 23 + 10 + 2 = 33 + 2 = 35

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+10 +2

35 33

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Year 2 – Addition methods

Partition into tens and ones and recombine Record as: 12 + 23 = 10 + 20 + 2 + 3 = 30 + 5 = 35

+10 +20+2 +3

0 30 35

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Yr. 1 - Subtraction

Objectives: Understanding subtraction as “taking away” Find a “difference” by counting up Use concrete and pictorial methods to

support the subtraction of a one-digit number from a one digit number or two-digit number

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Yr.1 - Subtraction

Understand subtraction as 'taking away'.

Can record 6 -1 as:

(1) Count how many strawberries are left after 1 has been taken away or eaten

(2) Count back on a number line

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Year 2 – Subtraction Objectives

Add or subtract mentally a one-digit number or a multiple of 10 to or from any two-digit number; use concrete and pictorial methods to add and subtract two-digit numbers.

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Year 2 – Subtraction Methods

Find a small difference by counting up42 – 39 = 3

42 39 40

+ 1 + 2

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Year 2 – Subtraction Methods

Use known number facts and place value to subtract (partition second number only)

37 – 12 = 37 – 10 – 2 = 27 – 2

= 25

372725

- 10- 2

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Year 1 Multiplication & Division

Multiplication Recognising multiplication as repeated addition Counting on in multiples of 2’s, 5’s & 10’s Recalling doubles of all numbers to at least 10

Division Grouping & sharing equally

Strategies: Using fingers, number line & cubes

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Year 2 – Multiplication

5 x 3= 15

3 x 5

5 + 5 + 53 + 3 + 3 + 3 + 3

Arrays

+ 3 + 3 + 3 + 3 + 3

0 15

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Year 2 – Division

15 ÷ 3 = 5 -3 -3 -3 -3 -3

150

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Thank you for coming!