What is already known on this topic? Since 2010, the proportion of U.S. 12th grade students who reported using marijuana during the preceding 30 days (21.4%) has surpassed the proportion reporting use of cigarettes during the preceding 30 days (19.2%).What is added by this report? During 1997–2013, the proportion of white, black, and Hispanic high school students overall who were exclusive cigarette or cigar users decreased 64%, from 20.5% to 7.4%. The proportion of white, black, and Hispanic students who were exclusive marijuana users more than doubled from 4.2% to 10.2%, and among cigarette or cigar users, marijuana use increased, with considerable increases identified among black and Hispanic students toward the end of the study period.What are the implications for public health practice? Despite significant declines since 1997, approximately 30% of white, black, and Hispanic U.S. high school students were current users of cigarettes, cigars, or marijuana in 2013. Policy and programmatic efforts might benefit from integrated approaches that focus on reducing the use of tobacco and marijuana among youths.