Private schools apply annually for approval from the Washington State Board of Education to operate as an approved private school. The application form is currently available online. As of March 16, 2020 the State Board of Education granted an extension for submitting private schools application out two weeks.
You have until April 15, 2020 to submit your application to the State Board of Education. You must file by that time to be approved at the May board meeting. School must be approved 90 days prior to the first day of school.