To explore how effective CPS (Classroom Performance Systems) are in the classroom, specifically for library instruction, this pilot study considered the question: "Does the use of CPS improve student retention of information presented in class as measured by pre-and posttest scores?" The use of pretest and posttest measurements for the retention of information attempted to assess the impact of instruction using CPS for a single session and the usefulness of CPS for the delivery of instruction, generally. The data collected included the results of a five-item pretest and a six-item posttest, completed by 48 freshmen college students. Although scores improved for both groups after instruction, scores for the group using CPS with instruction showed somewhat greater improvement than the non-CPS group. The author also discusses the role of instructional design in the development of the study and other considerations for future studies. (Contains 2 tables and 20 notes.)