Evaluation findings showed that the curriculum had almost no effect in changing students' attitudes toward drug use; however, four of the seven modules had a significant impact on improving students' knowledge of the biological bases of substance abuse. As a method of delivery, the video was consistently better at increasing students' knowledge compared with other delivery methods, and the workbook was the least effective. Students who were assigned to the video, Internet, or CD conditions for delivering information performed better than students in either the workbook or control conditions. There were no measured changes in knowledge or attitudes for three of the intervention modules, i.e., those that addressed genetics, consequences of substance abuse, and treatment of substance abuse. The findings of the current investigation made it difficult to determine why delivery format did not have an impact on students' gains in knowledge for these modules. Although significant gains in knowledge were measured as a result of curriculum participation, the fact that the control group also experienced knowledge gains detracted somewhat from the impact of the findings. Each delivery format featured a fictional up-and-coming teen pop band called "The Doubles," which is composed of a set of identical twins and a set of fraternal twins. As the students follow the band's adventures, they learn about the science of addiction. A total of 274 students (ages 8 to 10) enrolled in a rural school district 30 miles from St. Louis, MO participated in this study. The effects of the curriculum were measured with knowledge and attitude questions before and after program participation. 2 tables, 5 figures, and 32 references