The child takes out the cylinders, mixes them up, and returns them to the correct place.

The Knobbed Cylinders

The Knobbed Cylinders

Roberta Frosolini


The child develops the visual perception of dimension.



  • co-ordination of movement
  • one-to-one correspondence
  • left-to-right eye movement for future reading
  • finger strength for future writing




  • Ten cylinders decreasing in diameter


Language of comparison: Thick, thin, thicker, thinner, the thickest, the thinnest.

Control of Error

The apparatus itself provides correction; the child cannot complete the exercise without placing the cylinders in the correct sockets.


“[The child] exercises his hands in the delicate act of taking hold of the button with the tips of one or two fingers…” —Dr Montessori’s Own Handbook

Hold the cylinder block firmly by the two ends. Place it on front of the child, who should be sitting comfortably, whether on a floormat or at a table.

Hold the first cylinder, starting with the one on the left hand side of the block, with a delicate tripod grip (the grip used for holding a pencil), carefully remove it from its place. Quietly place the cylinder on the table.

Continue this way until you have removed all the cylinders and placed them randomly on the table.

Now pause for a few seconds, then look in the first socket on the left of the block and choose the matching cylinder. Replace the cylinders, one by one, in order of size, from largest to smallest. When you have finished let the child have a turn.