Stern Structural Arithmetic Kit Supplement

Catherine Stern, a physicist by training and the founder of a Montessori school in her native Germany, designed this apparatus. Stern and her husband were of Jewish descent, and emigrated to New York City in 1938 to avoid persecution by the Nazis. There she developed these materials, described in her 1949 book Children Discover Arithmetic. The equipment was used in preschools and later in primary schools.
This is a supplement to Stern’s Structural Arithmetic Kit A. It includes wooden cubes, rods, and cases, as well as paper cards and styrofoam squares. The painted cubes are 11/16” (1.8 cm.) on a side, and the rods are of integer multiples of this length. The rods are painted green (1), violet (2), white (3), brown (4), yellow (5), red (6), light blue (7), orange (8), black (9) and dark blue (10). There are ten rods of each color except dark blue, with 11 of these). There also are ten unit cubes in each of the colors white, red, dark blue, and black. Included is a unit box with 19 rods (as in the other kit). A grooved wooden number track reaches from 0 to 100. It is in 10 pieces held together with dowels, with two end pieces as well.
For teaching two-digit numbers,Stern designed a “dual board” that holds up to ten 10-rods in one square and up to 10 unit cubes in an adjacent groove. Two notched wooden “standards” hold up the dual board. To teach about hundreds, Stern used ten styrofoam pieces, each a 10x10 square. The kit also includes two sets of cards showing single digits, and a third set of cards showing two-digit numbers (the latter incomplete). Cards of the first set fold, and are intended for teaching multiplication. The other cards fit in grooved blocks, one designed to hold two-digit numbers and the other for three-digit numbers. All of these materials fit in a cardboard box.
The apparatus also includes a square wooden case, painted gray, called the 20-case, and used especially to teach the properties of the numbers from 11 to 20.
For related objects see 2005.0229.01. For related documentation, see nonaccession 2005.3100.
Currently not on view
Object Name
teaching apparatus
date made
Stern, Catherine
Physical Description
paper (overall material)
wood (overall material)
plastic (overall material)
overall: 25 cm x 43.5 cm x 43.5 cm; 9 27/32 in x 17 1/8 in x 17 1/8 in
ID Number
catalog number
accession number
See more items in
Medicine and Science: Mathematics
Arithmetic Teaching
Science & Mathematics
Data Source
National Museum of American History, Kenneth E. Behring Center


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