With our sense of smell we are able to perceive the ethereal state of natural matter when it is present in the air. A rose, for example, reveals its finest essence in its perfume. Through our sense of smell we come closest to matter in its outward, physical form. In the case of most animals, a well-developed sense of smell is a vital part of their instinct.
In contrast, the human sense of smell is quite underdeveloped. While there are people who are visually and audibly orientated, a highly developed sense of smell is rare.
We always tend to judge smells, to determine whether they are pleasant or unpleasant. Through their sense of smell, children develop their first impressions of what appeals to them and what doesn't. This is reflected when we say that something "stinks" or "smells fishy".
art makes sense
The younger the child, the more intensively it perceives things with all its senses. All materials it works with - paints, modelling wax, pencils or paper - should therefore be pleasant and appealing to its sense of smell.