Welcome to Years 1 & 2 Calculation Evening

Mental Methods  Years 1 & 2 use many practical methods to solve a variety of problems involving addition, subtraction, multiplication and division.  Children will learn to develop their mental strategies.  Emphasis on children developing their reasoning skills e.g. sometimes, always never. Convince me…, Prove it.

Addition

 Read, write and interpret mathematical statements using symbols +, -, =  Represent and use number bonds and related addition facts within 20 (know number bonds to 10 by heart)  0+10=10 1+9=102+8= 10

Using number bonds (number pairs) = = = 100

 =  =  10+10=

 Addition is commutative e.g = 13  3+10=13  13 =

Dienes

Partitioning ++ + 

Singapore bar model ks_addition_subtraction.html

Near doubles Think of then add 1

Add near multiples of 10 and adjusting Think of then -1

Bridging through

Subtraction

 Finding the difference between…  Provide children with a range of equipment. Teach them to explore different strategies.  6 - 2= ?

 Number line

Counting up  33 – 29 =

Partitioning 54 – 23 = 50 – 20 = 4 – 3 =

Using known number facts I know 7 – 2= 5 So =50

Adjusting the numbers, while keeping the difference 46 – 27 = Add 3 to both numbers 49 –30 =19

Multiplication

 Children should be familiar with times tables 2,5,10’s (rapid recall of these by the end of year 2)  Children should be very proficient at doubling and halving up to 20.  Recognise odd and even numbers.

 Use socks (link to odd and even numbers)

 Represent multiplication pictorially/ use concrete objects

 Multiplication linked to doubling and halving  Early stages of arrays

Arrays  5 x 3 =  3 x 5=

 Draw an array to show 6 x 5 =

Informal Methods  Multiplication is commutative 2 x 4 = 4 x 2

Applying and reasoning What do you know about 10? = = 10

Division

 Pictorial representation  8 ÷2 = 4

 15 ÷ 5 = 3

Thank you for listening