Written Calculation Methods for KS1

Addition

Step 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 = 42 Add multiples of 10 by going down a row on the 100 square.

Subtraction

Step 1 Find 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 2 Begin 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 =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 = 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

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=10 2.Addition can be done in any order 6+4=10 and 4+6=10 3.Subtraction facts from 10, if I know 6+4=10 then 10-6=4 4.Then this progression repeats for facts to 20 (16+4=20) and to 100 in multiples of 10 (60+40=100)

Any questions?