Here are some of our favorite quotes and ideas from Maria Montessori in her 1912 book, The Montessori Method:
"The little round stair is another game, in which a little wooden stairway, built on the plan of the spiral, is used. This little stair is enclosed on one side by a balustrade on which the children can rest their hands. The other side is open and circular. This serves to habituate the children to climbing and descending stairs without holding on to the balustrade, and teaches them to move up and down with movements that are poised and self-controlled. The steps must be very low and very shallow. Going up and down on this little stair, the very smallest children can learn movements which they cannot follow properly in climbing ordinary stairways in their homes, in which the proportions are arranged for adults."
Physical Environment, The Montessori Method, Ch. 9