Sammi has the same problem with scratching walls. Your cat might like the more natural feel a wall has, so I would suggest getting her a cedar scratching post. It's wood, so it will feel similar to a wall. Some cats just don't like to scratch sisal or carpeted posts. Sammi hates them.
I would spray bitter apple on the parts she is eating.
You can buy Soft Paws and put them on yourself, if you want to avoid taking her to the vet to do it. We put them on by ourselves and it works okay.
Also, she might be misbehaving out of boredom. I would try to have more interactive play time with her everyday. Try doing two 15 minute play sessions a day. If she feels like she's getting enough active play from you, she may not be so inclined to play naughty by herself.