Constraints in assessing the impact of animals in education

The primary purpose of this article is to delineate constraints researchers may encounter in assessing the impact of animals in education, even when u sing rigorous research designs. A case study is used as a framework for thi s discussion and consists of a project conducted In a pre-school setting, u sing a cross-over design to control for most threats to Internal and extern al validity. The project is presented first, with a brief description of th e goals and methodology of the project followed by a summary of the outcome s. A discussion follows of the constraints encountered in implementing and evaluating the project, including confounding variables and unanticipated, intervening events occurring during the course of the project. Finally, sug gestions are provided for addressing these types of constraints in future o utcome studies of the impact of animals in education. (C) 2000 Internationa l Society for Anthrozoology.