Scratching post plus some gentle tutoring did the trick for my two. I like that they have something to scratch - it looks comfy as fuck, they stretch while clawing stuff.
Also not a nut, nor a vegetable, nor a vegetarian. I'm all for a declawing ban. It is utterly cruel to value furniture over the wellbeing of a living creature.
If you've got nice furniture that you're not willing to sacrifice to a cat, DON'T GET A CAT. Mutilating a cat just so that you can be close to said cat is fucked up. Let it live with people who can take care of it without having to alter it.
Cats not having claws... They're defenseless animals without them :/ would you rather they bite you with their kitty germ mouths or claw you when they're telling you to fuck off