Digitor Arithmetic Training Apparatus

During the late 1950s and 1960s, American scientists and educators proposed using machines for instruction. Teaching machines and related programmed textbooks used a careful sequence of questions for teaching. Jerome C. Meyer and later William R. Hafel, both of Sunnydale, California, believed that it would be more efficient to use randomly generated problems. Given a problem, a student entered the answer. A correct answer elicited a new problem. These ideas were incorporated in this teaching device, the Digitor.
The instrument, introduced by the California firm Centurion Industries in 1974, used an Intel microchip and boasted a space-age look. It taught basic arithmetic. More recently, electronic calculators have become common at more advanced levels of mathematics teaching.
P. A. Kidwell, A. Ackerberg-Hastings, and D. L. Roberts, Tools of American Mathematics Teaching, Baltimore: Johns Hopkins University Press, 2008, pp. 259-260.
Currently not on view
Object Name
special purpose computer
special purpose computer1
date made
ca 1975
Centurion Industries Incorporated
Physical Description
plastic (overall material)
metal (overall material)
rubber (overall material)
overall: 25 cm x 19.8 cm x 19.8 cm; 9 27/32 in x 7 25/32 in x 7 25/32 in
place made
United States: California, Redwood City
ID Number
catalog number
accession number
Learning Arithmetic
Arithmetic Teaching
Science & Mathematics
See more items in
Medicine and Science: Computers
Learning Arithmetic
Arithmetic Teaching
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Gift of Centurion Industries Incorporated
Additional Media

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