Mental Maths Strategies Workshop 1: Addition and Subtraction 2014 - - PowerPoint PPT Presentation

Mental Maths Strategies Workshop 1: Addition and Subtraction 2014

1

Overview

Workshop 1

• May 2014
• Addition and

subtraction strategies

Workshop 2

• School year

2014/2015

• Multiplication and

division strategies

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Support Materials

PDST Workshop Booklet PDST Mental Maths Handbook

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What is Mental Maths?

• Sorting activity
• Teacher Reflection

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Key Messages

• 1. Concrete and pictorial exploration of number

is the foundation of mental maths strategy development

• 2. Pupils should devise, communicate and

reflect on various mental maths strategies

• 3. The teacher’s role is to facilitate

mathematical thinking

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Objectives

• To broaden participants perception of mental

maths

• To reflect on how pupils are encouraged to

engage in mathematical thinking

• To actively engage participants in identifying

and naming mental maths strategies for addition and subtraction

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8+8= 121+122=

In your class, which do your pupils use most often?

• rapid recall of known facts
• application of known facts

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Number Facts or Mental Maths

“Rapid recall of number facts is one aspect of

mental calculation but there are others. This involves presenting children with calculations in which they have to work out the answer using known facts and not just recall it from a bank of number facts that are committed to memory.” (Crown, 2010, p.12)

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Solid Foundations

• Being able to confidently add and subtract any

pair of two-digit numbers mentally is an important starting point for mental maths.

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6 aspects of maths that involve mental calculation

Recalling Facts Applying Facts Hypothesising and Predicting

Designing and Comparing Procedures Interpreting Results Applying Reasoning

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Crown, 2010

Teacher as Facilitator

• Starts by assessing the knowledge of the

group

• Information flows in many different directions
• Facilitators elicit a variety of methods from

pupils

• Facilitators encourage pupils to critically

evaluate solution methods

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A Range of Methods…

“To help children to learn and draw on a range

• f mental methods, you need to raise their

awareness and understanding of the range of possible strategies, develop their confidence and fluency by practising using the strategies, and help them to choose from the range the most efficient method for a given calculation.” (Crown, 2010, p.15)

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I just know it

Stages of Progression

• Counting Strategies – using object

counting (for example blocks or fingers)

• r verbal counting to determine the

answer.

• Reasoning Strategies – using known

information to logically determine an unknown combination.

• Mastery – efficient (fast and accurate)

production of answers.

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Arthur Baroody (2006)

Mental Strategies for + and -

COUNTING

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Name the strategy…

• 160 + 170
• 404 – 200

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Handbook p.19, 20

Name the strategy…

• 164 + 206
• 150 - 28

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Handbook p. 21

Name the strategy…

• 65 + 7
• 1.4 + 1.7

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Handbook p.21, 22

Name the strategy…

• 58 + 47 – 38
• 4.7 + 5.6 – 0.7

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Handbook p. 22

Name the strategy…

• 109 + 256
• 96 - 55

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Handbook p.23, 24

Name the strategy…

• 6.8 - 4.9

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• 5.7 + 3.9

Handbook p. 24, 25

Name the strategy…

• 6.30am + 40 minutes
• 15.20pm – 3h 40

minutes

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Handbook p.26 - 27

Name the strategy…

• 1088 – 975
• 124 – 97

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Handbook p.28-29

Name the strategy…

• 51 – 26
• 2448 – 298
• 209 – 151

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Handbook p.29 - 31

Addition and Subtraction Strategies

Counting forwards and backwards Doubles/near doubles Facts of 10 Bridging through ten(s) Reordering Partitioning by place value Compensating Bridging through 60 (time) Subtraction

• Think addition
• Keeping a constant

difference

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The Test !

No pressure You can work with a partner to figure them out

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Mastering the Basic Facts

Do:

1. Ask students to self- monitor 2. Focus on self improvement 3. Drill in short time segments 4. Work on facts over time 5. Involve families 6. Make drill enjoyable 7. Use technology 8. Emphasise the importance

• f quick recall of facts

Avoid:

1. Using lengthy timed tests 2. Using public comparisons of mastery 3. Proceeding through facts in

• rder from 0 to 9

4. Moving to memorisation too soon 5. Using facts as a barrier to good mathematics

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Van de Walle, p. 188

Steps to Success for Pupils with SEN…

• 1. Recognise that more drill will not work
• 2. Provide hope
• 3. Inventory – the known and unknown facts for

each student in need

• 4. Diagnose strengths and weaknesses
• 5. Focus on reasoning strategies
• 6. Build in success
• 7. Provide engaging activities for drill

Van de Walle (p.186/187)

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Reflect again

Activity 1 : Re-sort statements Activity 2: Reflection booklet pg 5

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PDST Supports

• Session 2 Term 1 2014
• www.pdst.ie