IANIMALS IN GENERAL and vertebrates in particular display little of their repertoire of behaviors in confined situations. Classroom observations of the behavior of Planaria, Daphnia, and Anolis often are less than rewarding for students. However, the problems encountered in observing organisms in their natural environments need not restrict the practical study of ethology in schools. The zebra finch, a popular aviary species introduced in Europe early in the nineteenth century, is easy to maintain in captivity. Its rich variety of behaviors are unaltered by domestication and their cause, consequence, development, and evolutionary significance are easy for students to interpret. Because so little attention has been given to the species' potential educational usefulness, this article focuses on the biology of the zebra finch for those teachers who wish to incorporate observations of this bird into their instructional programs.