First we learnt about 'whole' and 'part' in the context of objects.

We learnt that 'a whole' can also represent a group of objects. We can identify a part of a whole group and explain what a part-whole model is.

We understand that a ‘whole’ can be split into parts in lots of different ways but the total amount (whole) stays the same. We used our skills of subitising and our knowledge of the commutative to explain our thinking.