Sensorial

Geometric Cabinet

The geometric cabinet is designed to develop visual and muscular discrimination of shape, training the eye to understand the form. The cabinet itself is wooden with six drawers. Each drawer has six wooden squares. Each wooden square has a figure cut out, with a knob in the center by which to hold the insert. When the cut-out figure is lifted, the blue background of the drawer shows the shape of the cutout. The first drawer has six circles, varying in diameter from 5 to 10 cm. The second drawer has six variations of rectangles, beginning with a square, each smaller than the preceding one. The third drawer has six different types of triangles. The fourth drawer has six different kinds of regular polygons. The fifth and sixth drawers have different shapes, such as oval, ellipse, quatrefoil, trapezoid, right-angle trapezoid, rhombus, and parallelogram. There is also a demonstration tray with a circle, triangle, and square, the remaining squares being filled in with plain squares of wood. The child begins this exercise by gently removing a shape from the tray. He then traces the shape by starting at the lower left corner and running the first two fingers of his right hand around the outline. He then traces the frame with the same two fingers clockwise. He continues this procedure until all shapes have been traced and replaced. The child gradually learns to place the shapes on a solid form on a card, then on a thickly lined form on a card, then on a thinly lined form on a card, which is a precursor of writing. As the child grows older, he explores all of his environment at a progressively more refined level. The geometric cabinet provides for this with variations and extensions. The child may use combinations of two or more drawers or he can play matching games at a distance. The child also proceeds naturally to the metal insets, to holding a pencil, and then to actually writing.

Long Rods

The long rods are a series of ten rods 2 centimeters square but varying in length from 10 centimeters to 1 meter long. They are arranged on a mat with the longest rod at the top and carefully aligned on the left side. The purpose of this exercise is to isolate the dimension of length and to prepare the child for the math exercise of the number rods. Extensions of this lesson include creating a spiral with the longest rod still along the top edge of a mat on the floor. The child may then walk ever so carefully into and out of the spiral. Language development is “long/short”, “long/longer/longest”, and “short/shorter/shortest”. At home, you can reinforce this lesson by observing varying lengths of pencils, spaghetti, hair, etc.

Broad Stair

The broad stair is a series of ten wooden prisms 20 centimeters square down to 1 centimeter square. Sometimes they are painted brown and are called the brown stair. They are arranged on a mat to form a stair, beginning with the largest on the left and progressing to the smallest on the right. The purpose of the material is the visual and kinesthetic perception of thickness, to prepare the mind for mathematics by promoting the concept of volume, and to develop eye/hand coordination. Extensions of this lesson include stacking the prisms and corresponding the pink tower with the broad stair, laying them horizontally alongside each other. Language development for this exercise is “thick/thin”, “thick/thicker/thickest”, and “thin/thinner/thinnest”. At home, gradations of thickness may be observed using books, pasta (before and after cooking), paper, or fabric.

Cylinder Blocks

The cylinder blocks is a series of four smooth, wooden blocks with ten knobbed cylinders in a row along the top. The cylinders vary regularly by height or diameter or both. The first block increases by both diameter and height, progressing from short and thin to tall and thick. The second block increases by diameter only. The third block increases in height but decreases in diameter so that its progression is from short and thick to tall and thin. The fourth block varies by height only. The child is shown how to remove the cylinders carefully, using only the fingertips. This pincer movement is the same one he will eventually use to grasp a pencil. He learns concentration as he focuses his attention on just this one task. The very young child might at first use both hands to remove and replace the cylinders since the blocks are a long reach for his short arms. But eventually he will learn to reach across his body with his dominant hand to the opposite end of the block. This reaching across his body is an important development in laterality for the child, somewhat similar to learning to pattern when a child learns to crawl. As the child continues this work, his visual perception and visual memory are enhanced. Eventually the child will be able to merely look at a cylinder from any one of the blocks and place it in its correct position.

Extensions of this material include working with two blocks simultaneously, then three, then all four. When the child’s visual perception has progressed to this level, then he may be blindfolded and taught to use his tactile sense to place the cylinders. Language development here is the comparison between “thick/thicker/thickest”, “short/shorter/shortest”, “thin/thinner/thinnest”, and “tall/taller/tallest”. Descriptions such as “tall and thick” and “short and thin” may also be used.

At home, allow your child to concentrate as he maneuvers a rod into a jar or attempts to fit a shape into a slot in a shape sorter. Sometimes as adults, we shorten our children’s attention spans by well-intentioned advice or assistance. When we help where help is not needed or wanted, we unconsciously send the message that our child is not capable and we can frustrate his attempts at independence. Always wait until the child verbally asks for assistance. Even the youngest toddler can be taught to say “help”.

Knobless Cylinders

The knobless cylinders are four boxes of ten cylinders. Each set of box and cylinders is colored. These cylinders vary by height and diameter in the same way that the cylinder blocks varies. The yellow cylinders increase by both height and diameter. The red cylinders increase by diameter only. The green cylinders increase by height while they decrease by diameter. The blue cylinders increase by height only. The first presentation of this material is to arrange the cylinders from one box in a row decreasing by thickness. The child may then be shown how to stack the cylinders. Stacking the cylinders is quite difficult and requires excellent eye/hand coordination and fine motor development. The child must focus intently on his task and a long attention span is developed. Eventually, he will be shown how to use two or three sets together to create wonderful designs in rising and falling patterns of color.

Language development here is for the relationships between “thick/thicker/thickest”, “short/shorter/shortest”, “thin/thinner/thinnest”, and “tall/taller/tallest”.

At home, encourage your child to arrange things in ascending and descending order. As you travel about, observe how a building is created with descending sized cubes or how an ice cream cone has descending pods.

Stereognostic Bag

The stereognostic bag is a cloth bag approximately 7”x 9” with an opening on one side. Four or five objects familiar to the child are placed in the bag. He is shown how to place his hand in the bag and to identify an object without looking at it. He may then remove the object from the bag for all to see. The purpose of this game is to reinforce the muscle memory of shape. It develops mental vision and necessitates thinking. Because the child is conscious of “thinking” in the game, his awareness of how to think is increased. A certain amount of self control is also developed because the child must prevent himself from peeking before he guesses.

At home, you can encourage your child in various thinking processes. Take him through a step-by-step analysis of a question you think he can figure out for himself. Help him to apply something he already knows to a new question. Or play foolish “what if?” games to stimulate creativity. Blindfold and guessing games are tremendous fun for the child when his parent joins in.