Children begin to informally investigate joining groups to add.
They explain that adding is starting with more than 1 group, and joining groups together.

We’ve swapped the order that we introduce adding and taking away!
Our work in schools has shown us that children develop understanding of taking away better if it is introduced before adding. Before children start selecting 2 numbers and making 2 groups, the develop understanding of selecting 2 numbers and thinking about ‘which number they could make a group of that would give them enough to take away a group of the other number’.