Sentence:  Dr. Clark has served as teacher and principal in Oklahoma <WSD>high</WSD> schools , as teacher and athletic director at Raymondville , Texas , High School , as an instructor at the University of Oklahoma , and as an associate professor of education at Fort Hays , Kan. , State College . 
Meaning of the word marked with <WSD> tags:  a public secondary school usually including grades 9 through 12