The presentation of sophisticated atomic theory (quantum mechanics) in secondary chemistry texts is not accompanied by sufficient evidence or applications to promote its rational acceptance as determined by a model of conceptual change. Eight secondary chemistry texts were analyzed for four elements associated with a conceptual change model: dissatisfaction, intelligibility, plausibility, and fruitfulness. These elements were not present in sufficient quantities to promote conceptual change, i.e., to have quantum mechanics rationally accepted over simpler atomic models such as the Bohr theory. Recommendations include modifying future textbooks to include conceptual change elements; having secondary chemistry teachers emphasize these elements beyond the presentation in their textbooks; and using the conceptual change model to analyze other instructional materials, especially those presenting scientific theories. J Res Sci Teach 34:535--545, 1997.