Sensorial comes from the word sense or senses.

Children and even adults learn best and retain the most information when they engage their senses. Many of our favorite memories are associated with one or more of our senses: for instance, the smell of a summer night campfire or a song you memorized the lyrics to with a childhood friend. Now, when your nostrils and eardrums are stimulated with those familiar smells and sounds respectively, your brain triggers a flashback memory to those special times.

For a child, senses play an important role in learning. The child is able to concentrate on the refinement of all his senses, from visual to stereognostic.

The stereognostic sense is the capability of recognizing an object without seeing it, hearing it, smelling it, or tasting it. An example of how the stereognostic sense is used might be the ability to find and turn off your alarm clock in the morning with your eyes still closed.

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Children learn by way of not five senses: touch, sight, smell, taste, or hearing that we know of . They learn by way of visual discrimination i.e. learning that colors, sizes and shapes differentiate one thing from another. Spatial sense or as they call in Montessori "Proprioception" helps a child develop their unconscious perception of movement and orientation.

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The purpose and aim of Sensorial work is for the child to acquire clear, conscious, information and to be able to then make classifications in his environment. Montessori believed that sensorial experiences began at birth. Through his senses, the child studies his environment. Through this study, the child then begins to understand his environment. The child, to Montessori, is a “sensorial explorer”.

Through work with the sensorial materials, the child is given the keys to classifying the things around him, which leads to the child making his own experiences in his environment. Through the classification, the child is also offered the first steps in organizing his intelligence, which then leads to his adapting to his environment.

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Montessori’s materials for the Sensorial work came from her own observations and from ideas and materials from the French doctors Itard and Seguin.

Unlike the material used for Practical Life, this material has either never been seen or never been used by the child in his everyday life.

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With this said however, the child will receive no new experiences through the use of the material. This was purposefully thought through in order to give the child what he knows, but might not yet realize, and to then refine his knowledge.

In order to do this, the material is presented in a specific way or in a specific pattern: the child learns to match the similar things, then he is shown how to grade the material based on its quality, and then he receives the language related to his work.  

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Presenting the material to the child in this way allows him to fully understand the concept of his work.

All of the Sensorial materials were designed keeping the same ideas in mind.