I would add Whitman.
I third the suggestion to look at Colorado. Our oldest son is an avid snowboarder and mountain biker. He visited friends in Denver a couple of times after he was out of school and working. Soon after he started looking for a job in Denver and moved there 3 years ago, buying a house this year. The skiing and snowboarding is very close and very good. There is a lot of great hiking and amazing mountain biking in the summer. He wishes he had looked there for school but is there to stay now.
As LakeWashington said, you will pay out-of-state tuition at any of the state universities you are thinking about, and they are expensive for OOS students. You actually might pay less if you found a good liberal arts college where your son might get merit aid or need based aid.