The abstracts and critical analyses of research in this document were prepared and compiled to add to the fund of information on the effects of hand-held calculators on achievement and learning. Since many persons find it difficult to secure original copies of all research studies, the expanded abstracts should provide specific information frequently not included in the brief abstracts found in other publications. The critical commentary prepared by each abstractor pinpoints particular strengths and weaknesses noted for each of 36 studies. This document is proferred with the hope that other researchers will profit from analyses of the flaws and strengths in the design of each study. Almost all of the studies comparing achievement of groups using or not using calculators either favor the calculator group or (in about equal number) reflect no significant differences. Areas researched include decimals, problem solving, estimation, division, computational skills, proportion, general mathematics, business mathematics, chemistry, economics, low achievers, and retention. (Author/MP)