The Abacus and the Numeral Frame - Early Use of the Numeral Frame
Various forms of the abacus have been and still are used in arithmetic teaching. From the late 1830s, many American schools purchased numeral frames. These demonstration devices had one or more wires strung with beads that moved crosswise, as on a Russian abacus. The instrument apparently developed independently in France and in England, and was brought to the US from both countries. Teachers used numeral frames to introduce young students to counting, addition, subtraction, multiplication and fractions.