The New York Hall of Science, in collaboration with the Lawrence Hall of Science, is producing and evaluating an application of recently available technology, the random-access audio player, which offers the promise of improving the effectiveness of learning at science-technology center interactive exhibits. The audio "tours" that are being produced and tested will have varying degrees of branching and layering appropriate to the nature of each exhibit unit design. A "highlights" audio tour will be created for the Lawrence Hall of Science and an audio tour focusing on a single group of light, color, and vision exhibits will be created for the New York Hall of Science. The audio tours will be tested with two different categories of audience at each site: the general public on weekends and schools groups on weekdays. Alan Friedman, Director of the New York Hall of Science, will be the Principal Investigator. The Lawrence Hall of Science will be represented by Brooke Smith. The audio tours will be written and produced by Steve Tokar, the producer of Science Today a daily radio science program on the CBS radio network. Beverly Serrell, Director of Serrell & Associates, will conduct the evaluation of the audio tours at each site.