Year 4 teacher Josie Clark demonstrates how she uses very specific language to explain to her pupils the difference between one and negative one.
In the past, Josie taught negative numbers using analogies like bank accounts or thermometers, but some children were confused.
Watch as her pupils practise new words such as "negative" and "subtract". They demonstrate their understanding by moving cards, which helps them to visualise the actions of adding, subtracting and dividing negative numbers.
Maths adviser Richard Dunne is also on hand with some handy hints and tips.
