The child lives in a 3 dimensional world. It is an important step to give her the 3 dimensional symbols for the numbers.
She manipulates and assimilates the 3D symbols.
These are stored in her mind and later she will accept the flattened version of these images in the form of the printed numbers.
There is always a true 3 dimensional reference present in her mind and her physical memory.
Without this her mind may try and produce 3 dimensional images from the flatted printed numbers.
Sometimes the flattened numbers move and come off the page as the child attempts to bring them into her 3 dimensional world.
Adult supervision needed at all times. Small items. Danger of choking.