Surprisingly, none show up in the Eugene area, nor near Salem. However, at least a dozen are around Portland. For the traditional general children s outdoor camp, check out Camp Collins east of town, run by the YMCA.Other possibilities are the skiing and snowboard camps which are at their peak in the summer. http://www.highcascade.com/ http://www.mthood.com/
See if the Civilian Conservation Corps has worksites around there. http://www.opb.org/programs/oregonexperi��
I heard the Oregon Zoo is offering something for the teens but not sure if it is volunteer or payed work. You should contact them, that would just be a way to cool job.