You can get out of 11/12 grade in Washington state. Community college is really what hs should be though.
http://www.k12.wa.us/SecondaryEducation/CareerCollegeReadine...
Washington's constitution states that It is the paramount duty of the state to make ample provision for the education of all children residing within its borders.[1] It is interesting how this manifests in practice.
[0] http://www.k12.wa.us/GATE/Truancy/default.aspx
[1] http://leg.wa.gov/LawsAndAgencyRules/Pages/constitution.aspx