First Montessori school in the USA: Children and Teacher working on the number rods (aka red and blue rods) in the year 1912:

A staple Montessori didactic material, that has been around for over 100 years and to this day it is a very valid piece of learning: introduction to quantity 1-10 and their corresponding number names. The lesson is to associate the names with the correct quantities. When used with the printed numerals the child learns to associate the figures with the actual quantities 1 through 10.

Through this exploration the student also develops the concept of sequencing numbers

Another great little free nugget download here:

Author: Brigitta Hoeferle