This article describes a study of team teaching in high school biology. The study is generally concerned with the rapid rate of growth of knowledge and the acceptance of the assumption that there is a direct relationship between a teacher's mastery of a subject and the teacher's ability to teach. The variety of team teaching developed in the study is based on the belief that the field of knowledge covering high school biology is extensive and that it would be more effective if teachers specializing in different phases, such as physiology, genetics, or plant morphology will team up.