Since the early-2000s, deliberative democratic theory has influenced the debate on teaching. Proponents of deliberation in education have argued that deliberative communication as a teaching model enhances both subject knowledge and democratic virtues among students. However, empirical support for this assumption is weak. The aim of this article is to empirically test the assumptions made by the proponents of deliberative teaching. This study uses a field experimental research design. The study was carried out in a civics course in Swedish upper-secondary schools in both vocational programs and programs preparing students for ensuing studies. To some extent, the results support the hypothesis derived from deliberative theory. Deliberative teaching seems to enhance democratic virtues among students in vocational programs.