Many preservice teachers confront their own lack of confidence and actual mathematics phobia for the first time in their math procedures classes. This study was designed to explore the application of a confluent education intervention, a model based on the premise that all learning is accompanied by an affective as well as a cognitive component, to the problem of improving the disposition towards mathematics of 70 student teachers enrolled in a fifth-year multiple subject teaching credential program at the University of California. Using the framework of constructivist theory as a foundation, the paper discusses the effects of prior experience on affective disposition towards mathematics and teachers' sense of self-efficacy. Data were collected in three stages following "The Mathe Teakst Buk," an intervention that involves students in a simulation to reconstruct prior experience by coupling it with affective processing. Results indicate types of changes in disposition and self-efficacy experienced by students after the confluent intervention. A complete description of the intervention is appended. (Contains 29 references.) (LL)