No, calculators have no negative impact on learning.
The studies done thus far show that calculators only have a positive impact on learning. Only one exception was the grade 4 class from a 1986 study.
A Meta-Analysis of the Effects of Calculators on Students Achievement and Attitude Levels in Precollege Mathematics Classes
The findings of 54 research studies were integrated through
meta-analysis to determine the effects of calculators on student
achievement and attitude levels. Effect sizes were generated through
Glassian techniques of meta-analysis, and Hedges and Olkin's (1985)
inferential statistical methods were used to test the significance of
effect size data. Results revealed that students' operational skills
and problem-solving skills improved when calculators were an integral
part of testing and instruction. The results for both skill types were
mixed when calculators were not part of assessment, but in all cases,
calculator use did not hinder the development of mathematical skills.
Students using calculators had better attitudes toward mathematics
than their noncalculator counterparts. Further research is needed in
the retention of mathematics skills after instruction and transfer of
skills to other mathematics-related subjects.
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Effects of hand-held calculators in precollege mathematics education: A meta-analysis
The findings of 79 research reports were integrated by meta-analysis
to assess the effects of calculators on student achievement and
attitude. Effect sizes were derived by the method invented by Glass
and tested for consistency and significance with inferential
statistics provided by Hedges. At all grades but Grade 4, a use of
calculators in concert with traditional mathematics instruction
apparently improves the average student's basic skills with paper and
pencil, both in working exercises and in problem solving. Sustained
calculator use in Grade 4 appears to hinder the development of basic
skills in average students. Across all grade and ability levels,
students using calculators possess a better attitude toward
mathematics and an especially better self-concept in mathematics than
students not using calculators
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The Effects of Non-CAS Graphing Calculators on Student Achievement and Attitude Levels in Mathematics: A Meta-Analysis
Forty-two studies comparing students with access to graphing
calculators during instruction to students who did not have access to
graphing calculators during instruction are the subject of this
meta-analysis. The results on the achievement and attitude levels of
students are presented. The studies evaluated cover middle and high
school mathematics courses, as well as college courses through first
semester calculus. When calculators were part of instruction but not
testing, students' benefited from using calculators while developing
the skills necessary to understand mathematics concepts. When
calculators were included in testing and instruction, the procedural,
conceptual, and overall achievement skills of students improved.
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