This activity is included in many elementary school science texts in the unit on the human body. As an introductory activity in the study of basic anatomy, this activity works well for students with visual impairments because of its tactual and auditory components. The threading of the tubular shoe lace shows how the vertebrae in fact surround the spinal cord.
The macaroni accurately represent the separate vertebrae, which are difficult to discern tactually on a skeleton. Moving the backbone constructed without the cushioning discs, produces a grinding sound as bone rubs against bone. The backbone made with discs moves more easily and quietly.