Explorations involving the use of mini electronic calculators in connection with mathematics instruction were conducted with two fifth-grade classes, two second-grade classes, and one third-grade class. Explorations are being continued with third-grade classes (last year's second grade classes). Selected activities and related materials are described and illustrated. Limited empirical data suggest that pupils encounter no consequential problems with the mechanics of using simple four-function, algebraic-logic calculators in routine contexts, and that pupils likely will elect not to use calculators in situations where their use is unnecessary or of no particular advantage. Departing from elementary-school mathematics programs which usually emphasize binary operations and their properties in relation to distinguished sets of numbers, project explorations have moved increasingly toward content interpretations in terms of unary operations and operators, and properties associated with them. (Author/SD)