Written Calculation Methods for KS1

Addition

AdditionStep 1•To find one more than a number.

•To combine groups of up to 10 objects and label.

•To count on using fingers.

•To count on using a number line starting with the largest number.

• Step 2• Begin to use the + and = sign to record number

sentences.

Step 3• Use a number line and

then an empty number line to add a 2 digit number and a 1 digit number.

• Use a hundred square and then an empty number line to add a 2digit number and a multiple of 10.

• 32 + 10 = 42

• Add multiples of 10 by going down a row on the 100 square.

Subtraction

Subtraction Step 1Find one less than a number.

Take objects away and label up to 10.

Take away on fingers.

Count back using a number line.

Draw objects and cross out.

Step 2Begin to use the – and = sign to record number sentences.

Step 3• Find the difference with numbers up to 20, by

counting up, using visual objects, bead strings and towers of unfix.

• Write finding the difference number sentences using the – and = sign appropriately.

• 14-11=3 the difference between 11 and 14 is 3.

Step 4• To subtract a 1 digit number from a 2 digit

number by counting back on an empty number line using a 100 square as a visual prompt.

.

Step 5•Subtract 10 and multiples of 10 from a 2 digit number by counting back. •Use 100 square and teach the rule of jumping up

1 row when subtracting 10.

Multiplication

Step 1•Counting in 10’s, 2’s and 5’s.

•To know the doubles and corresponding halves to 10 and then 20.

Step 2•To understand multiplication as repeated addition.

Arrays.2 x 4 =

+ + +

4 x 2 = +

Arrays on a number line

Using a multiplication grid. When using a multiplication grid we will teach the children to use the grid vertically for first number and horizontally for second number as this follows the same principle of arrays.2 x 4 = 8

Division

Division

• Step 1• Count back in 10’s, 2’s and 5’s.

• Know halves of numbers to 10 and then 20.

Step 2• To understand division as grouping.

• Understand division as repeated subtraction using a number line.

• 18 ÷ 3 = 6• Reinforce division as grouping through arrays.

• 6 ÷ 3 = 2 • 6 divided into groups of 3 is 2.

Number facts

1. Addition facts to 10, 6+4=102. Addition can be done in any order

6+4=10 and 4+6=103. Subtraction facts from 10, if I know

6+4=10 then 10-6=44. Then this progression repeats for

facts to 20 (16+4=20) and to 100 in multiples of 10 (60+40=100)

Any questions?