We examined direct and interaction effects of learners' characteristics (cognitive ability, prior knowledge, prior experience, and motivation to learn) and classroom characteristics (videoconferencing and class size) on learning from a 16-week course. A 2x2 quasi-experimental design varied the class size between large (approximately 60 students) and small (approximately 30 students) and between traditional classes with the instructor always present and classes taught using a videoconferencing system with the instructor present at each site every other week. Theory regarding instructor immediacy was used to predict that larger and videoconferenced classes would have negative effects on learner reactions and learning, but that highly motivated learners would overcome the negative effects on learning. Interactions between videoconferencing and motivation to learn, and class size and motivation to learn, were found in support of the theory. Research and practice implications are discussed. (Contains 6 tables, 2 figures, and 2 notes.)