I've been compiling an extensive list of Portland area resources if you want to organize a field trip for your homeschool group, or hire an educator for a presentation. It's finally ready! You will find it here: http://stagbeetlepower.blogspot.com/p/portland-area-field-trips.html or click on the page link on the top right of the blog. Since virtually any place might welcome a field trip if you ask, there's no way to make this list truly complete. I'd love to learn about any additions you'd like to suggest! I'm really amazed by the extent of resources we have available to us, and definitely plan to share this list with anyone who questions that homeschoolers are able to give their kids a terrific education outside of classroom walls.
Please share this list if you find it useful!