The effects of accompanying lectures with computer-mediated PowerPoint presentations or PowerPoint generated overheads on students' self-efficacy, attitudes, course performance, and class-related behaviors were examined. Two Introduction to Developmental Psychology sections were initially taught with lectures accompanied by either overheads or computer-mediated presentations. The teaching format was switched halfway through the semester. Students reported higher self-efficacy and more positive attitudes toward the class with computer-mediated presentations. They also claimed that the website was more interesting and useful under these teaching conditions, indicating a halo effect of the computer-mediated presentations. However, the teaching format did not appear to affect course-related behavior, such as performance on exams, class attendance, participation in class discussions, or course website usage.