We have been working on addition and subtraction methods. We have learned about partitioning into tens and units and partitioning to take a number to the nearest multiple of 10.
It is very important you know what the next multiple of 10 up or down would be. For example, the next multiple of 10 up from 17 is 20 and the next one down in 10. We have used number lines to help us subtract using this knowledge.
Below are some photos of the strategies we have been using.