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.

Date Made: ca 1975

Maker: Centurion Industries Incorporated

Location: Currently not on view

Place Made: United States: California, Redwood City

Web Subject: Mathematics


See more items in: Medicine and Science: Computers, Learning Arithmetic, Science & Mathematics, Arithmetic Teaching


Exhibition Location:

Credit Line: Gift of Centurion Industries Incorporated

Data Source: National Museum of American History

Id Number: 1986.0507.01Catalog Number: 1986.0507.01Accession Number: 1986.0507

Object Name: special purpose computerspecial purpose computer1

Physical Description: plastic (overall material)metal (overall material)rubber (overall material)Measurements: 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

Guid: http://n2t.net/ark:/65665/ng49ca746a1-3cd2-704b-e053-15f76fa0b4fa

Record Id: nmah_334387

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