The effects of student-directed activity-based learning (SDABL) were examined in two high school chemistry classes. Students in the SDABL class were given pretest results, a list of standards to be mastered, and a chart of learning activities categorized by difficulty level. They selected activities to meet their needs and preferences. Significantly greater achievement gains and more consistent participation were found in the teacher-led instruction class. Overall, most students believed they learn better by teacher-led instructional methods. SDABL may have the potential to be effective in high school chemistry classes if more student preparation is part of the strategy.