The Three Period Lesson is very simple and clear for the child. The teacher does not ask the child to name the object until she is sure he can recognise it.
Give the child a large and a small object and say ‘This is large’ and ‘This is small’
Ask the child to indicate which is large and which is small.
Show the child the large object and ask ‘What is this?’, then show him the small object and ask ‘What is this?’