- Ten wooden prisms. (The length of the prisms is the same, but the square cross-section increases by one centimeter; the smallest one being 1cm square, the second being 2cm square, etc.) - the largest being 1dm square.
- A floor mat.
This is an individual exercise, which is done on the floor on a floor mat. (Note: Work cycle to be observed)
The child is invited to build the stair.
- The Directress first shows the child how to carry the wooden prisms to the floor mat.
- For the smaller prisms, the child may use one hand to hold the prisms. For the larger ones, the child may use two hands. It is important to hold the prisms across their breadth so that a muscular impression of the size is felt.
- All the prisms are placed at random on the floor mat.
- Exercise 1: Directress then shows how to build a stair, beginning with the largest prism and placing the next largest prism just next to it. (Note: Move the prism by sliding them. Hence, plan before hand how to place the prisms on the mat)
- When completed, invite the child to view it from the top and ask: "What does it look like?" The child may offer some suggestions and opinions.
- Exercise 2: Directress may further invite the child to run through the stair with their fingers sliding down the slope of the prisms from top to bottom. Directress then takes the narrowest prism and slides it along the stairs from top to bottom.
- Directress may use the largest and the smallest wooden prism and uses the Three Period Lesson to teach the terminology "Broad and narrow"
- When completed, return the wooden prisms back to the shelves, by taking the largest prism first.
Control Of Error
The visual sense acts as a control of error, but the act of running a hand either up or down the stair helps the child realize through the sense of touch where there is an error.
Points Of Interest
If the child experiences difficulty in doing this exercise, then it is recommended that we start with three or four prisms:
- The smallest.
- The largest.
- Three of four alternate ones.
These blocks are considerably heavy for a child. He must make an effort with his little hand, and this stretches and strengthens it. After making repeated use of the blocks, a child's hand finally adopts automatically the precise position necessary for covering the with of each block. In other words, a child develops a muscular memory for definite graduations of space.
Once the child can do the Pink Tower and the Broad Stair, he may use both pieces of material together and discover any relationship between them such as the similarities and differences in the dimensions between the cubes and the prisms. After the child tells you what he has discovered remember to give him any appropriate language.
- Develop the child's visual and muscular perception dimension.
- Develops the child's coordination of movement and fine motor control.
- Prepare the child, indirectly, for mathematics by giving the child experiences in comparison, grading and seriation with prisms.
- Provide basic language- important in mathematics.
- Build the stairs with the wooden prisms standing vertically.
- Use the prism to build a tower. Needs the Directress assistance because it may reach quite high and the Directress probably needs to stand on a chair to place the prisms on top of each other. Explain to the child the danger of doing this exercise.
- By combining the Pink Tower and Broad Stair. Build the Broad stair standing vertically as in (1) and then placing the Pink tower cubes on top of the prism.
- As in (3) but building it horizontally on the floor mat.
- Play a game with the children. This can be done in a group. Select three different sized prisms and lay them on the table. Directress makes a request, for e.g. "Bring me the broadest prism", "Bring me the narrowest prism" or the Directress selects one of the prism and then says " Bring me a broader/narrower prism than this",...etc. The child will have to bring the prism required to the Directress.