When questioned regarding their sources of environmental information, many people cite television as the major contributor. Recent research has in fact identified a relationship between scores on aquatic information tests and the reported number of Cousteau documentaries seen on television. This study assesses the knowledge and attitude changes resulting from home viewing of a Cousteau Society documentary on marine mammals and compares these changes with those resulting from a science teacher's presentation of the documentary's script. A pretest-posttest-delayed posttest comparison group design utilized an instrument based on specific program content. Results indicate that comparable presentations in either medium can result in increased and retainable knowledge. Attitude changes were apparent in the television treated group but not among those receiving classroom treatment.