Presentation on theme: "‘I didn’t learn to do it that way!’ Beaconside Parents’ Maths Workshop – Addition and Subtraction 5 th March 2013."— Presentation transcript:
‘I didn’t learn to do it that way!’ Beaconside Parents’ Maths Workshop – Addition and Subtraction 5 th March 2013
Maths! What’s your experience? What are your first thoughts? Do you panic? Have you any negative experiences?
A world without numbers! Be positive about number!
Children learn + and - by: Being confident about number – seeing that numbers are everywhere. Using and experiencing a range of resources. Using and experiencing a range of methods so that they can decide which is the best method to use: Pictures; mental calculation - with or without jottings; structured recording; calculator How ? Understanding and using a selection of mental strategies Knowing number bonds ( ie 7+3=10, 18+2= 20) Place value ( understanding the order and the value of digits including zero as the place holder) Money ( everyday money- calculating change) Problem solving
Resources Number line Counters Online games Place value cards Unifix sticks Number square Subitising activities
Subitising Subitising is the ability to recognise dot arrangements in different patterns without counting. It is a fundamental skill in the development of number sense and will help in the ability to add and subtract as well as recall number bonds quickly. We can learn: there are 5 dots. 5 is more than 4 5 objects can be separated in to a set of 2 and 3 5 counters, no matter how arranged, still retain the same numerical quantity The oral name for a set of 5 things is ‘five’
Subitising: Activity 1 Play – show me (digits and numbers) Fantastic for fast recall of number bonds – support with + and – facts without the need for counting.
Place Value – Activity 2 We use place value cards in combination with unifix cubes and 100 squares to recognise values of numbers. i.e. Use the place value cards to make the number 245 Partition the number. Children understand 245 = 200+40+5 =245 Zero is important- it is the place Holder and keeps the number in the Correct column.
Activity 3 –addition with jottings using partitioning 25 + 33= 58 Success Criteria: Step 1: partition numbers ( tens 20 + 30) (units 5+3) Step 2: add up the Tens ( 20 + 30 = 50) Step 3: add up the Units ( 5+ 3 = 8) Step 4: add both (50 + 8= 58) 55 + 26 ( 50 + 20= 70) ( 5+6= 11) 70 + 11 = 81 Key skills – adding 10s mentally – can you use a number square to spot patterns when adding multiples of 10 to any number?
Activity 4: Back to number bonds: 1+9 = 10 and 9+1=10 10+90 = 100 and 90+10 = 100 100+900 = 1000 and 900+100=1000 0.1 +0.9 = 1 and 0.9+0.1 = 1 Look for the patterns. Let the children discuss. Now have a go! Show me! See the relationship between subtraction and addition 10–9 = 1 10-1 = 9 Now have a go! Show me!
Activity 5 – Number squares - spot the patterns.
Number lines are an important tool for addition and subtraction Addition = count on Subtraction is count back Subtraction = difference Addition = more than Subtraction = less than NUMBER LINES: They show the order of numbers from left to right. They are used to count on and back in 1s (Nursery+) Counts on and back in 1s, 2s, 5s, 10s (Reception and Year 1+) Count on and back in 100s (Year 2/Year 3+) Count on and back in 1000s(Year 4+) Count on and back in decimals/fractions (Year 5+)
Number lines in action: Addition Activity 6 - Have a go…
Empty Number lines (Addition): Children will begin to use their knowledge of partitioning and counting on in larger steps as they become more confident. Have a go with a partner.
Number lines (Subtraction): Starting in Reception/Year 1 They use number lines by counting back from the start number. The number line should also be used to show that 6 - 3 means the ‘difference between 6 and 3’ or ‘the difference between 3 and 6’ and how many jumps they are apart.
Empty Number lines ( Subtraction) : Counting back From Year 2 Have a go!
Empty Number lines (Subtraction): ‘Finding the difference method’ – Counting on (Y2 – Y6) Success criteria Put the smallest number on the left Put the largest number on the right Subtract by finding the difference and counting on in steps you feel comfortable. Example: Have a go!
Now on to the formal methods… Addition: Year 4 onwards:
Working towards Formal Method – Subtraction (End of Year 3)
Leading to Formal method: Year 4 onwards:
Remember: Be positive about maths! Children have a choice – allow them to play with numbers and choose their own methods. Support and share – let them discuss! Maths can be practical – Food, cooking, coins and money, measuring. Online games and resources can help.
Online games Children love games to engage their learning. Try some of these: