Malcolm Knowles is attributed with developing the most cogent model underlying the assumption that teaching adults should differ from teaching children and adolescents. His andragogical model is based on the premise that adult learning differs from preadult learning. Two studies have examined whether teachers do actually use a different style when teaching adults. Respondents in both studies reported they spend less time on discipline and giving directions, provide less emotional support, structure instructional activities less tightly, and vary teaching techniques more. Follow-up classroom observations in one study did not verify the self-reported differences in teaching behavior. That study did find that a nontraditional, less-formal room arrangement did lead to the use of a more student-centered approach; teachers with more formal training in adult education tended to use student-centered approaches the least; and the more flexible and responsive teachers were less experienced, female, secondary-level, and those who taught personal enrichment classes. Some considerations for practice emerged from the studies: determine the purpose of the teaching-learning situation, provide opportunities for teachers to practice learner-centered methods, and select teachers on the basis of their potential to provide learner-centered instructional settings. (YLB)