An introduction to positive and negative numbers. Cartoon-style numbers initially form a line from 0 to 9. The negative numbers 1 to -9 then join the line in the correct sequence. The clip continues with 3 added to -7, and then added to -4, and so on, to show how the result of the addition becomes more positive each time.

First broadcast:
14 September 2007

Use as an introduction to negative numbers. After watching the clip, create a horizontal number line (or have one already prepared) for the pupils to further practise. Try starting at the number 9 and subtracting 5 until you reach the negative numbers. Ask the children which negative number would come next. Alternatively, start at -9 and add 4 each time. Ask the children to record their ideas on mini whiteboards to ensure the whole class understands. You could progress onto a vertical number line and ask the children for real life reasons for using negative numbers.