The Philadelphia City Schools engaged in a four-year program to develop and test dual audio television, a way to help children learn more from the massive amounts of time they spend watching commercial television. The format consisted of an instructional radio broadcast which accompanied popular television shows and attempted to clarify and amplify the vocabulary concepts that were presented. Supplementary audio broadcasts were developed for"Gilligan's Island,""The Flintstones," and "Scooby Doo," and studies were conducted to measure their levels of utilization and their effects on vocabulary development. Results showed that the audience size was insufficient to justify national networking, and the instruction was effective for only a portion of the intended audience. (EMH)