It’s time to learn about the commutative property of addition through magic sums. Many children in my class are getting the hang of the ‘count count count’ strategy. A quick demonstration with a string of beads followed by lots of discussions was enough to convince them that the addends in an addition sum can be reversed, but the answer is the same. The children enjoyed doing the ‘magic trick’ and turning the string of beads round to magically reverse the sum. It is important children understand this before they move onto the strategy ‘start with the biggest number’.
- Verbalise the mathematical process
- Using concrete resources allows children to see for themselves that nothing has been added or taken away when the sum is reversed.