Effects of an advance organizer on three strategies used in teaching a disjunctive concept

Vita.The focus of the study was the effect that various teaching strategies have on the attainment of a disjunctive concept; that is, a concept that contains at least one of its relevant attributes. The study investigated the relative efficacy of affixing an advance organizer to three teaching strategies comprised of characterization and exemplification moves. An advance organizer (A) is information given to students prior to instruction that relates the new material to be learned to previously learned material. A characterization move (C) discloses the properties of the concept while an exemplification move (E) identifies members or nonmembers of the concepts' referent set. There were six teaching strategies used in this study. One strategy, designated the E Strategy, consisted of ten examples and three nonexamples all accompanied by justification. A second strategy, designated the EC Strategy, consisted of the E Strategy followed by a C move. The C move was the definition of a particular mathematical concept. A third strategy, designated the CEC Strategy, consisted of the same C move used in the EC Strategy followed by the EC Strategy. The remaining three strategies; designated the AE Strategy, the AEC Strategy, and the ACEC Strategy, all consisted of the same advance organizer followed by the E Strategy, the EC Strategy, and the CEC Strategy respectively. Each strategy was randomly assigned to one of six treatment groups. A seventh treatment group was designated a control group. To evaluate the effect of the treatments, a pretest and a posttest was administered to all seven treatment groups.