This investigation built upon previous studies that compared effectiveness and efficiency among instructional methods. Instructional effectiveness and efficiency were compared among three conditions: an incremental rehearsal, a more challenging ratio of known to unknown interspersal word procedure, and a traditional drill and practice flashcard method. Six first-graders who demonstrated basic word reading difficulties participated in this study. Instructional effectiveness was measured by cumulative words read accurately on next-day retention probes, and instructional efficiency was measured by cumulative rate of words retained per minute of instructional time. Results revealed that incremental rehearsal was the most effective method for students as a group, whereas the traditional drill and practice was the most efficient method on reading performance. Students as a group maintained and generalized reading more words that were taught in the incremental rehearsal condition. Implications for school psychologists who work with educators to design, implement, and evaluate instruction are provided. (Contains 2 tables and 2 figures.)