This study examined the impact of an infant-feeding classroom activity on the breast-feeding knowledge and intentions of adolescents living in Nova Scotia, Canada. One hundred twenty-one students attending two high schools were administered one pretest and two posttest questionnaires. Students were arbitrarily assigned to a control or intervention group. The intervention group partook in a 60-minute classroom activity on infant feeding. Findings indicated that students in the intervention group demonstrated significantly greater breast-feeding knowledge at Posttest 1 and at 10 weeks postintervention. Students in the intervention group reported a significantly greater intention toward breast-feeding their own future children; an increase was sustained at 10 weeks. These findings suggest that adolescents' knowledge of and intention toward breast-feeding may be positively influenced during their teen years. School nurses are well positioned to support and encourage the inclusion of breast-feeding content in school curricula to enhance adolescents' knowledge and intentions toward breast-feeding. (Contains 3 tables.)