Fort Osage High School is a high school located at 2101 N. Twyman Rd. in unincorporated Jackson County, Missouri, in the Kansas City metropolitan area, adjacent to Independence. It belongs to the Fort Osage R-1 School District and serves a section of northern Independence. It currently serves approximately 1,500 students from grades 9-12. It is named after the Fort Osage National Historic Landmark along the Missouri River in nearby Sibley, Missouri.