As for Crater Lake at that time of year you should be able to get up to the lodge and at least see the lake. The south access road is open all year for the most part. You may be able to take some of the rim drive around the lake. You can watch the website for the lake and get updates then decide. I have also been there in mid August and woke to a couple of inches of snow too.
Collier State Park makes for a fine day trip up to the lodge. Like the others have said the logging museum is worth it if any of you like old iron. It is self-guided and the price is right. My then 10 year old grandson became a fair logger while we were there on summer.
Another place is to see is the Lava Lands and the lava cave, about a mile plus walk into it. Worth it too.