Horton, S. (1985). Computational rates of educable mentally retarded adolescents with and without calculators in comparison to normals . Education and Training of the Mentally Retarded , 20 (1), 14–24. https://www.jstor.org/stable/23877279

[no doi reported]; Also accessible online at http://psycnet.apa.org/psycinfo/1985-23845-001

Students completed single skill math probes in two conditions: paper-and-pencil and calculator.

Participants were sixteen junior high students. Eight students were performing at grade level, and eight students (50% of total sample) had cognitive disabilities and had obtained grade level scores between 1.5 and 2.1 on the Standford Diagnostic Math Test-Form A.

The dependent variable was scores (number of fully correct answers) on math probes in four areas (addition, subtraction, multiplication, division).

Eight students without disabilities completed math probes without calculators to establish a mean level of performance. Students with cognitive disabilities completed math probes in paper-and-pencil and calculator conditions. Students with cognitive disabilities did not produce a single correct answer in the paper-and-pencil condition for subtraction, multiplication, and division problems, even after training. They also got all problems in these areas incorrect in the calculator baseline condition (prior to training). However, following training with using the calculator, these students' percentage of problems correct per minute increased to 84-96%. The authors conclude that calculator responses were superior to pencil-and-paper responses for students with cognitive disabilities. Limitations and future directions for research were discussed.