These tasks demand mathematical thinking. They are designed to be used to support with observation and assessment. The idea is that the children discuss in pairs and groups and the adult observes, prompting and probing where necessary, taking notes on: the facts they know; the skills they choose to use; the maths words they use; how they describe/explain; also if they link/apply/make reference to other areas of maths or other contexts.
They will help you to find out where there might have been lost learning as well as identify gaps that will need filling. Use the information to specifically target need..