A young child meets the world around him through the constant use of all his senses. To examine a new object, a baby will look at it, hold it in his hands to feel the texture and weight, shake it, lick it, or even try to bite it. Montessori felt that this was the ideal time to give children equipment which would sharpen their senses and enable them to understand the many impressions they receive through them.
Each of the Sensorial Materials isolates one defining quality such as color, weight, shape, texture, size, sound, smell, etc. The equipment emphasizes this one particular quality by eliminating or minimizing other differences. Thus, the sound boxes are all the same size, same shape, same color, and same texture; they differ only in the sounds which are made when the child shakes them.