Studying a programmed textbook was compared with studying a conventional textbook to determine which method leads to better performance on a content examination. Both texts covered similar material on operant psychology. In a setting where 12 teaching assistants each taught 2 discussion sections with enrollments of about 22 students, 1 section studied the programmed text, and the other studied the conventional text. At the end of the semester, all students took an examination which contained several types of items. The results of the experiment favored the programmed text in that, for all 6 objective types of items and for 5 out of 8 essay items, the level of performance of the programmed text group was higher than the conventional text group (p < .05 or better from the analysis of variance).