Parents Numeracy Workshop Strategies for Addition & Subtraction

The National Numeracy Strategy Good teaching incorporates: An oral/ mental starter Main teaching focus Plenary ICT Assessment for Learning as well as Assessment of Learning

Assessment for learning Shared learning intention Planned success criteria Pupil self-assessment Talk about and explain maths Written and oral feedback

Supporting your child at home Think about: The value of children explaining the task to their parents Ways in which the parent supports the child’s learning through listening, encouraging and confirming The quality of work – content and presentation

What can a numerate child do? By the age of 11 they should :  have a sense of the size of number and where it fits into the number system  know by heart addition and subtraction facts to 20, multiplication and division facts to 10x10, doubles and halves, complements to 100, multiply and divide by 10 and 100  use what they know to figure out answers mentally

What can a numerate child do? (cont.)  calculate accurately and efficiently, both mentally and on paper, using a range of strategies  recognise when it is appropriate to use a calculator- and when it is not- and be able to use one effectively  explain their methods and reasoning using correct mathematical terms  judge whether their answers are reasonable and have strategies for checking them where necessary

The aim  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.

 Mathematics is mainly an activity of the mind, and written calculations are an aid to that mental activity.  The Numeracy Strategy aims to develop children’s mental strategies and then written methods that derive from and support mental methods. Learning written methods is not the ultimate aim.

We want children to ask themselves: Can I do this in my head? Can I do this in my head using drawings or jottings? Do I need to use an expanded/compact written method? Do I need a calculator?

– – – How do you add and subtract?

Mistakes children make:

…….and more:

These equations are carried out horizontally which leads to

= 76 Addition

= Addition

Subtraction Imran has 43 conkers; he gives 24 away to his friends. How many does he have left? 43 – 24 = conkers

Subtraction Sam has saved 93p, Amy has 55p. How much more money does Sam have than Amy? 93 – 55 = p more

Subtraction 8.23 – 4.55 =

Subtraction A sports stadium holds 9010 spectators people attend a football match. How many empty seats are there? empty seats 6000

Parents Numeracy Workshop Strategies for Multiplication & Division

57 x 278 ÷ 2 43 x ÷ 2 36 x ÷ 4 18 x  10 8 x 1917 ÷ 5 34 x 75.4 ÷ 6 How do you multiply and divide?

Mistakes children make: 76 x x r

Multiplication Early stages Counting in groups of Arrays or repeated addition 3x2 or 2 x3 But also 2X 3= 6 3 x 2= 6 x3=6

Multiplication Later Partition 23 x 4 20 x 4 = 80 3 x 4 = 12 92

Multiplication More formal methods 47 x 8 = x x 46 = x

Multiplying using more traditional methods 27 X X

Division early on Groups of and sharing But also 6÷3=2 6÷2= 3 ÷2= 3

Division 375  

First on a number line 87 ÷ subtract 7x10 or 7 ten times We have subtracted seven 12 times and have 3 left so… 87 ÷ 7 = 12 r 3 subtract 7x2 or 7 twice

A shop notice states that there are 87 shopping days to Christmas. How many weeks is that? (x10 weeks) (x2 weeks) 3 So it’s 12 weeks (and 3 days) of shopping to Christmas.

432 school children are going on an outing. If each bus takes 15 passengers, how many buses will be needed? (x20 buses) (x6 buses) 42 So we need 29 buses or 28 buses and some cars! -30 (x2 buses) 12 (people left)

Parents Numeracy Workshop Division: mental & written methods Division: mental & written methods

Understanding relationships between multiplication & division 17 x ? = 34 ? -:- 5 = 90 ? x 4 = x ? = 8000 ? x 0.5 = :- ? = 32 What operations did you use?

Using informal pencil and paper methods to support, record or explain divisions Self adhesive stamps come in sheets of Estimate how many sheets you would need to buy if you wanted 500 stamps. 2.How would we work it out exactly?

“Chunking” method Subtracting multiples of 24 from 500. Answer

How many coaches would be needed to take 780 people on coaches which hold 42 people each? How could we use the chunking method to answer this question?

Rounding up or down after division, depending on the context Calculator activity: 500 -:- 24 = What does the decimal part mean?

How many CDs at £11.99 each could you buy with £50? Estimate? Use a calculator What does the decimal part represent? Is there enough money to buy 5 CDs?

Strategies for problem solving Read the problem Understand the problem Choose the operation and estimate the answer Solve the problem Answer the question Check the answer

Identify and use appropriate operations to solve word problems involving numbers and quantities 89 children are camping. There are 3 tents that each take 9 children and the other tents take 4 children. How many tents taking 4 children are needed, and how many tents are needed all together? Estimate and record working