It is Washington D.C., but worth the mention if for no other reason that the fact that someone homeschooled - not in public or private school - won the regional.
"His winning research project was a computer algorithm that involved geolocation, a project he started a year and a half ago in Walkersville, where he is a home-schooled senior." [Frederick County teen wins regional science competition].
The Siemens Foundation competition "supports science, technology, engineering and mathematics (STEM) education." See the 2011 regional finalists. While you are at it - see also The Most Impressive High School Kids Graduating This Year. Peruse The 50 Best Colleges In America.
No - Oregon hasn't a mention.