Today we will be subtracting crossing 10.
For the first time, children will be introduced to subtraction where they have to cross ten.
This small step focuses on the strategy of partitioning to make ten.
Children should represent this using concrete resources or pictorially to begin with.
Ten frames and number lines are particularly useful to model the structure of this strategy - encourage them to draw these. This supports children as they move towards using them as a mental strategy.
How can you partition a number to help you subtract?
How does using the counters help you to see this strategy?
How does using a number line help you to see this strategy
Can you think of another way to represent this problem?