A teacher educator took over a high school physics teachers' class for a semester in exchange for the physics teacher taking over his university physics methods classes. The paper presents the perceptions of people involved in the experience. Students at both schools accepted the situation well. University students, invited to observe their university teacher at the high school, found it difficult to criticize his expectations as unrealistic, since he was out teaching high school every day. Some students felt free to criticize his teaching since they had been asked to observe; others hesitated because they were not used to criticizing teachers' work. Students had some difficulty finding value in repeated observations of one teacher. The teacher found student comments helpful. He decided that teaching one class a day while also teaching beginning teachers shifted his expectations for preservice education. He rethought the structure of preservice teacher education to make it more applicable to future classroom teaching. Three appendices offer an excerpt from a recorded after-class discussion with class observers, student comments showing different perceptions, and comments from a meeting with a graduate student who had videotaped a lesson. (SM)