[Drolefille]

Pardon the non-sisterly advice, but I'm a big fan of the "strip her room of anything fun and make her time outs in there" method. You physically pick her up and put her in there instead of trying to explain to her why she's in time out. Cause she knows.

And if she can open doors put one of those plastic doorknob covers on there so she can't get out on her own. (My mom used them to keep us out of the linen closet with the cleaning supplies and medicine in it, I assume they're still around somewhere)

That way time-out means something and isn't just time where she a)gets to play in her room or b) gets attention... she's left alone and can't watch/interact with you until her time is up.