A guide to adding and subtracting directed numbers
How do you introduce arithmetic with negative numbers in your classroom?
A number line?
Temperatures (like in this Standards unit resource)?
Or a good-old fashioned series of exercises (like these from the CIMT)?
Simon Jowett explores another method in his article 'A guide to adding and subtracting directed numbers' which looks at how 'charged spheres' (or counters) can be used, based on a concept development lesson from the Mathematics Assessment Resource Service- a resource with a strong focus on developing conceptual understanding.
You can find more resources that explore the four operations using positive and negative numbers in our Secondary Mathematics resource page.