Session 2 Addition and Subtraction

Why is it all so different today? A desire to do something different to counter the nations phobia around mathematics Development of understanding of effective methods to teaching mathematics since mid 1990s Exploration of effective approaches from some of the most successful education systems in the world Extensive research and trialling

There is no “right” way to work! Children exposed to a range of methods – if you get an answer, then the method works. Methods selected will depend upon the situation and the numbers involved, including when to use calculators. Efficiency is as important as accuracy. Children make decisions about methods and draw on a range of strategies and approaches when applying Maths is context. Children in same class could be using different methods to others depending on their ability, confidence and stage of mathematical development.

Total of 11

101 Down

Domino totals

The Numberline!!

The Numberline!!

The Numberline!!

Expanded Addition Try this method with these!!

Towards the Standard Method Towards the Standard Method

The Standard Method - Decomposition Linked initially with use of images and practical apparatus to secure understanding of how place value is being used in the calculation Lots of stages where children can make errors Not always the most efficient method to use If children can obtain an answer using another method, that is OK.

Can I do this mentally? Shall I use a written method? Which written method is most appropriate to use for these numbers?

I’m going to partition the numbers.

= 30 and and 7

and and 7 =

I start with the units, so I need to take away 7 small cubes. But I only have 3 of them. I’ll break up one of the 10s into 10 units. 30 and and 7 =

I’ve now got 2 lots of 10, so that’s 20, as well as 13 units, so let’s write it down to show what I am doing. 30 and and 7 20 and and 7 ==

Now I can take away 7! 30 and and 7 20 and and 7 ==

and and 7 20 and and 7 6 = =

Now I can take away 10! 30 and and 7 20 and and 7 6 ==

and and 7 20 and and 7 10 and 6 ==

and and 7 20 and and 7 10 and 6 = 1 6 = =

There will be examples like this… 75 – 32 where no exchange is needed, but partitioning is still useful as children are more successful at working with tens and units separately = =

Next stages will involve increasing the number of digits in the numbers (HTU, the ThHTU), working with apparatus, then without, to ensure children are secure with place value before moving on to the final stage. Often this would be taught side by side with the more expanded method so that children can se how they relate.

= = =

Why the additional steps?