high schools. One class in each school was randomly selected as a treatment group and followed the individualized instruction procedures described as Individually Diagnosed and Prescribed. The other two classes served as control groups and were taught by a traditional lecture-discussion method. The same teacher taught both classes in each school. The study was limited to one academic year, 1973-74, when the students were in ninth grade. Participation in the study was restricted to those students who selected algebra over general mathematics as a ninth-grade mathematics course. All ninth-grade students were required to choose one course or the other. The students had all been in a modified continuous progress learning model in mathematics in eighth grade. Students originally selected for participation in the study were excluded if their parents did not grant them permission to participate. These students were replaced by randomly selected alternates. Five students were unable to complete the study because they moved to another attendance area. Variables on which the experimental and control group were com pared were confined to achievement on a criterion-referenced, locallywritten algebra achievement test, attitudes toward mathematics, algebra grades, number of senior high school mathematics courses elected prior to graduation, and cumulative mathematics grade point in those elected courses. Two teachers, one in each building, taught the algebra classes in the study. Each teacher taught one experimental and one control class * Significance greater than or equal to .05 level.