Riverside, CA. The Sherman Institute, now known as Sherman Indian High School, is a historic, off-reservation boarding high school in Riverside, California, originally established by the U.S. government for Native American youth to assimilate them into mainstream culture through vocational and academic training, evolving from the Perris Indian School starting in the late 1890s. While it has a complex history marked by forced assimilation and cultural suppression, today it operates under the Bure