Dysmenorrhea is a problem that girls and women face and often manage themselves with or without support from health professionals. A cross-sectional, descriptive study was conducted among adolescents with dysmenorrhea (N = 150) in Ile-Ife, Nigeria. The aims of the study were to determine their knowledge of menstruation and primary dysmenorrhea, assess the severity of pain they experienced during an episode of primary dysmenorrhea, and determine the management strategies they adopted. A pre-tested semi-structured questionnaire was used to collect data. Findings revealed the adolescents had a knowledge deficit regarding menstruation and dysmenorrhea, 58% of respondents reported pain between face 4 and face 10 on the Faces Pain Scale and the majority used inappropriate methods to manage primary dysmenorrhea. School nurses are able to assist adolescents and their mothers in proper management of primary dysmenorrhea. (Contains 2 tables and 2 figures.)