The impact of the educational programs of zoos on the recreational visitor is addressed in this report. Unobtrusive or nonreactive research methods were employed as primary evaluative techniques by graduate social science students conducting six research projects at the Los Angeles Zoo. These studies were designed and implemented to examine: (1) visitor turning preference; (2) determinants of holding power of zoo exhibits; (3) reading signs at zoo exhibits; (4) children's reactions to animals in a petting zoo; (5) the stereotypes zoo visitors may hold about selected animals; and (6) intergenerational communication. It is suggested that nonreactive measures are particularly appropriate for these types of evaluation studies because they do not impose on visitors or require their cooperation, and because they reduce problems with sampling and response bias. (A review of the literature pertaining to education in zoos is also provided.) (ML)