I'll second what others have said, the bulk of the river is tough for bank access in the summer. You can do quite well tossing a spinner pretty much all year, but you have to pick your spots. If you have access to a boat or raft, floating the canyon tossing spinners can be a lot of fun for young anglers.
Otherwise, there isn't a bunch of accessible creek fishing for trout in this state. Rock Creek can be good, but it gets pounded and theres 3 times as many rattlesnakes. Lots of little creeks in the NE corner of the state have brookies in them. The Kettle River can be fun, but access is tough. Same with the Methow. You get the idea.