I tried that with a sheet of plywood outside with Zenobi. I don'tknow what it meant to her, but she went beserk wanting to chew on my hand. I had to go hide until she calmed down.To get them to scratch it, scratch it with your nails and say your cats name/s.
Or you can pick them up and get their front two paws and scratch it with them.
Hope she starts to use it!