The purpose of this study was to compare the effects of two treatment variables, mastery and aptitude, on two outcome variables, achievement and retention, as measured by researcher-constructed tests. Seventeen classes of seventh-grade geography students were taught an instructor-developed geography unit with either mastery or nonmastery…

The major purpose of this study was to compare self-instructional mastery and nonmastery treatments to determine if there are differences in learning, retention, and time-to-testing of high, middle, and low aptitude students. Twenty grade 7 classes from the Savannah-Chatham County School District served as the experimental population. Students…