How maths is taught – the number line

At an early stage children are introduced to the number line. This is a simple line of equally spaced numbers starting a 0, and progressing to the right 1,2,3 etc.

It is a simple matter to add numbers by counting on. To add 3 to 3. put a finger on 3 and count on 3, arriving at 6.

Similarly, counting back is used for subtraction. To subtract (or “take away”) 4 from 11, place a finger on 11, and count 4 to the left, arriving at 7.

Theoretically there is no limit to the extent of the number line, but in practice numbers larger than about 20 will not fit on a page, and if printed on a strip, the strip becomes unwieldy