Proper asthma management in schools is important in achieving optimum asthma control in children with asthma. The National Heart, Lung, and Blood Institute (NHLBI) has developed guidelines on classroom asthma management. We conducted a systematic review to examine teacher knowledge of the NHLBI guidelines on asthma management in the classroom. We searched PubMed and EMBASE using search terms “asthma management,” “teacher(s),” “school teacher,” and “public school.” The inclusion criteria were articles published in English from 1994 to May 2014 that focus on schools in the United States (US). From 535 titles and abstracts, 9 studies met inclusion criteria. All studies reported that school teachers did not know the policies and procedures of asthma management. Teachers relied on school nurses to handle medical emergencies. Some studies identified that lack of full-time school nurses was a barrier to asthma management. Only one study showed directly that classroom teachers were not following the NHLBI guidelines on asthma management. Our literature review revealed that US teachers do not know the NHLBI guidelines on asthma management in the classroom. Future research should focus on interventions targeted toward training classroom teachers on asthma management as per NHLBI guidelines to ultimately improve asthma management in schools.