Since Time-Immemorial Tribal Sovereignty - High School Curriculum
As history teachers, you know the State Legislature in 2015 passed a law requiring history teachers to incorporate Native American lessons in history courses, and to specifically tie this integration with local tribes. This link takes you to the high school curriculum developed by OSPI.
There are several links listed under this section at OSPI. There are videos, lessons, primary documents, and a listing of Native American tribes you may contact. Scan the left side of this web page for tabs that will take you to these additional sources.