The Knobbed Cylinder is a Sensorial activity designed to help children in making distinctions in their immediate environment. This engages the senses of touch and sight. This activity consists of 10 different cylinders with ‘knobs’ used to hold each object using the pincer grip. Each cylinder fits into a specific hole on a solid block of wood. The different variations of the Knobbed Cylinders, allows children to challenge different perceptions of preliminary mathematical concepts, such as weight and size.