The purpose of this study was to determine the short-term impact of inquiry-oriented teaching materials on high school students' understanding of consumer education concepts and practices. In addition, the study sought to ascertain if a comparative advantage exists in offering consumer education courses at the preservice and the inservice levels of instruction. Data collected and analyzed in the study were fit into linear regression equations, one for each of the eleven models employed in testing the hypothesis underlying the central problem. The Consumer Information Test (CIT) and the Test of Economic Understanding (TEU) were used to measure high school students' understanding of consumer education and economic knowledge. Study findings revealed that the inquiry-oriented teaching materials positively affect students' understanding of consumer education concepts and practices and that the traditional treatment of consumer education subject matter is less effective than the inquiry mode of instruction. (Author)