The novelty of deaf student teachers teaching normal ninth grade biology classes may increase motivation to learn subject matter if sign language lessons are oriented toward specific kinds of knowledge. Since Gallaudet University (Washington, D.C.) places deaf undergraduate student teachers in schools with normal hearing students, the effects of this interaction can be studied so the program can better serve both students and deaf student teachers. This study investigated the impact of sign language lessons by a black deaf student teacher, using an interpreter, on the achievement scores of ninth grade biology classes. Students were also given an attitude questionnaire at the end of the 8-week study. The study indicates that deaf student teachers, when teaching normal hearing students, should give sign language lessons at the beginning of each class period and these sign language lessons should be carefully prepared as a tool to interact with students regarding subject matter. The lessons may improve personal relationships more than increase achievement. Appendices include hand sign language aids, an achievement test sample and questionnaires. (Author/CW)