This study is an assessment of the effect of three criterion mastery levels and aptitude on the achievement, retention, and attitude of seventh grade students using a population geography text. The three criterion levels used were 90 percent, 80 percent, and 70 percent of the correct responses on each of 41 lessons in "Population Growth in…

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…